;-NRLF 


THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 

PRESENTED  BY 

PROF.  CHARLES  A.  KOFOID  AND 
MRS.  PRUDENCE  W.  KOFOID 


PRESENTING 

A  FAMILIAR  METHOD  OF  TEACHING 

THE 

CHEMICAL   PHI  JCIPLES 

AND     ' 

OPERATIONS 

OF    THE    MOST    PRACTICAL    DT£LITV 

TO  FARMERS,    MECHANICS,    HOUSEKEEPERS  AND    PHY 

SICIANS  ;    AND    MOST    INTERESTING   TO 

CLERGYMEN    AND    LAWYERS. 


INTENDED  FOR  SCHOOLS  AND  THE  POPULAR  CLASS-ROOM, 


THIRD   EDITION. 


BY  AMOS  KATON. 


ALBANY: 

PRINTED    AND    PUBLISHED    BY    WEBSTERS    AND    SKINNERS, 

1828. 


NORTHERN  DISTRICT  OF  NEW- YORK. 


L.S. 


BE  IT  REMEMBERED,  That  on  the  twentieth  day  of  February,  in 
the  forty-sixth  year  of  the  independence  of  the  United  States  ot* 
America,  WEBSTERS  &  SKINNERS,  of  the  said  district,  have  de- 
posited in  this  office  the  title  of  a  book,  the  right  whereof  they  claim 
as  proprietors,  in  the'words  following,  to  wit : 

"  Chemical  Instructor;  presenting  a  familiar  method  of  teaching  the 
Chemical  Principles  and  Operations  of  the  most  practical  utility  to 
Farmers,  Mechanics,  Housekeepers  and  Physicians  ;  and  most  inter- 
esting to  Clergymen  and  Lawyers.  Intended  for  Schools  and  the  Po- 
pular Class  Room.  By  Amos  Eaton. 

In  conformity   to  the  act  of  the  Congress  of  the  United  States,  entitled  "An  act 


for  the  encouragement  of  learning,  bv  securing  the  copies  of  maps,  charts  and  books, 
to  the  authors  and  proprietors  of  such  copies,  during  the  times  therein  mentioned  :" 
and  also  to  the  act.eutitled  "  An  act  supplementary  to  an  act  entitled  '  An  act  for  the 


encouragement  of  learning,  by  securing  the  copies  ot  maps,  charts  and  books,  to  the 
authors  and  proprietors  of  such  copies,  during  the  times  therein  mentioned,'  and  ex- 
tending the  benefits  ihereof  to  the  arts  of  designing,  engraving,  and  etching  historical 
and  other  prints." 

RICHARD  R.  LANSING, 
Citric  of  the  N.  District  of  Neat-York. 


NOTICES 

TO  BE  PREFIXED  TO  THE  SECOND  EDITION. 

Although  tliis  is  announced  as  the  second  edition,  it 
might  have  been  entitled  the  seventh;  for  it  had  been 
published,  in  substance,  under  the  title  of  Chemical 
Note-Book,  five  times  before?  it  assumed  the  present 
form  and  title. 

I  believe  it  is  known  to  all 'within  the  narrow  limit  of 
circulation,  to  which  this  book  is  destined,  that  I  have 
devoted  a  large  proportion  of  my  time  and  attention  to 
the  simplification  of  chemical  experiments,  for  the  last 
nine  years.  During  this  period,  1  have  given  more  than 
thirty  full  courses  of  lectures  on  chemistry,  with  from 
six  to  eight  hundred  experiments  at  each  course';  and 
have  endeavoured  to  improve  my  method  at  every  step 
in  each  course. 

Every  change  which  the  reader  will  find  in  this  edi- 
tionj  is  the  result  of  experience.  All  the  experiments 
are  described  precisely  as  I  have  frequently  performed 
them  ;  and  as  1  have  often  caused  them  to  be  performed 
by  students  in  my  presence.  , 

The  whole  object  of  my  course  of  instruction  being 
the  practical  application  of  science  to  the  common  con- 
cerns of  life,  1  give  no  experiments  on  rare,  doubtful,  or 
useless  substances  ;  and  avoid,  as  far  as  possible,  all 
hypothesis  of  a  merely  speculative  kind. 

The  valuable  works  of  Thompson,  Ure,  Brande,  Mur- 
ray, A<  cum,  Henry,  Davy,  Gorham,  and  others  ;  and 
the  smaller  works  of  Cotting,  Cutbush,  Comstock,  &c. 
together  with  the  translations  of  Lavoisier,  Fourcroy, 
&c.  as  well  as  the  essays,  and  editions  of  foreign  works, 
published  by  Silliman,  Cooper,  Hare,  &c.  must  all  be 
contained  in  the  library  of  the  thorough  chemist.  But  I 
venture  to  assert,  that  any  one,  or  all,  of  these  works 
will  not  form  even  a  tolerable  guide  for  a  course  of  chem- 


4  NOTICES, 

icaJ  experiments  adapted  to  the  wants  of  the  farmer,  the 
mechanic,  or  the  housekeeper.  Neither  is  this  such  a 
work  as  I  couid  wish  to  put  into  their  hands  ;  but  it 
comes  as  near  it,  as  I  am  at  present  prepared  to  make  it. 

It  is  much  to  he  regretted,  that  most  of  the  latest  cele- 
brated treatises  on  chemistry,  have  so  large  a.  proportion 
of  their  pages  devoted  to  th  >se  useless  compounds,  which 
can  never  profit  the  scholar  nor  Ihc  practical  man.  Par- 
ticularly those  endless  compounds  with  chlorine  and 
iodine,  which  may  be  equally  multiplied  and  extended 
with  any  other  substance.  This  is  surely  trifling  with 
the  richest  stores  of  human  knowledge.  Put  such  works 
into  the  hands  of  a  student,  and  tell  him  to  place  full 
confidence  in  the  authors,  he  would  form  strange  views 
of  the  science.  He  would  imagine,  that  the  chloridic 
and  iodic  theory  of  Davy  constituted  the  whole  science 
of  chemistry  :  and  that  all  further  knowledge  of  the  sub- 
ject should  be  pursued  as  a  convenient,  though  not  very 
important,  appendage  to  chlorine  and  iodine.  And  even 
admitting  all  Davy's  speculations  to  be  well  supported, 
are  not  those  idle  speculations  as  unimportant  as  any  of 
the  smallest  mites  of  human  knowledge  ?  I  would  as 
soon  set  a  student  to  commit  to  memory  all  the  amulets 
of  the  dark  ages,  or  the  number  of  ways  in  which  the 
letters  of  the  alphabet  can  be  arranged. 

In  this  edition  I  have  prefixed  a  few  general  remarks, 
with  a  short  account  of  the  natural  history,  to  each  chem- 
ical principle.  I  have  separated  the  rationale  from  the 
illustration,  in  the  three  first  classes  of  chemical  princi- 
ples. The  analysis  of  soils,  minerals,  mineral  waters, 
&c.  1  have  placed  after  organic  substances. 

A.  JEATON, 

EEHSSELAER  SCHOOL, 
Trey,  JV.  Y.  Feb.  6, 1826, 


NOTICES 

FOR  THE  THIRD  EDITION. 

As  two  full  editions  of  this  little  hook  were  sold  in  a 
very  short  time,  without  any  exertion  on  the  part  of  the 
bookseller  or  author  ;  its  simple  arrangement  and  quaint 
style  seem  to  have  been  sanctioned.  I  shall  therefore 
make  no  alteration  in  the  plan,  nor  materially  enlarge 
the  book.  A  few  corrections,  and  some  extension  oi  ifie 
head,  applications,  are  nearly  all  the  reader  is  to  expect. 

This  enquiry  has  often  been  made  :  "  Since  this  little 
book  is  intended  for  schools  and  the  popular  class-room 
only,  and  has  never  been  noticed  in  any  public  journal, 
why  are  more  copies  of  it  sold  than  of  any  other  work 
on  the  subject  of  chemistry,  published  since  it  ap- 
peared ? 

I  answer  this  enquiry  by  an  extract  from  a  letter, 
\\rittenbythefrank  ingenuous  professor  of  chemistry 
in  one  of  our  learned  institutions. 

**  I  will  thank  you  to  request  Messrs.  Websters  and 
"  Skinners  to  send  me  three  dozen  Chemical  Instruc- 
"  tors.  For,  like  the  professors  of  many  of  our  public 
"  institutions,  though  Thompson,  Brande,  Henry,  Gor. 
"  ham,  Davy,  Murray,  and  other  large  books  with  great 
<*  names,  are  set  forth  as  the  text-books,  I  conduct  my 
"  lectures  and  give  my  experiments,  according  to  your 
«  directions.  Though  1  <lo  riot  acknowledge  myself  de- 
"  pendant  on  this  duodecimo  of  260  pages  ;  yet  it  is  my 
<(  only  safe  guide  for  experiments.  I  intend  now  to  put 
"  it  into  the  hands  of  every  student,  with  some  sufficient 
"  apology  to  be  borrowed  from  the  neighboring  profes- 
«  sors." 

The  professor  in  another  public  institution,  says  :  "  I. 
f(  should  not  be  able  to  go  through  with  the  labor  of  a 
<(  course  of  chemical  experiments,  on  account  of  my 
I*  feeble  state  of  health,  had  you  not,  by  your  simple 


b'  NOTICES. 

"  method    described   in  the   Chemical   Instructor,    so 
"  greatly  reduced  the  labor  of  preparation." 

I  cannot  consent  to  enlarge  the  work,  according  to 
the  advice  of  some  of  my  friends.  I  have  long  been  con- 
vinced, that  the  greatest  improvement  which  could  now 
he  made  in  our  colleges,  would  be  effected  by  introduc- 
ing small  text  books,  in  which  the  substance  of  volumin- 
ous, works  should  be  judiciously  condensed. 

AMOS  EATON. 
Troy,Mareh  28,  1828. 


(   r   ) 

PORTABLE  APPARATUS. 

Pneumatic  cistern.  For  an  economical  course  of  instruction,  such 
as  that  proposed  in  the  following  work,  a  wooden  box,  three  feet  long, 
eighteen  inches  deep  and  eighteen  inches  wide,  will  be  sufficient.  It 
is  made  of  pine  plank,  so  arranged  that  the  grains  of  the  wood  all  run 
in  the  same  direction  ;  that  all  the  pieces,  constituting  the  cistern, 
may  swell  and  shrink  uniformly.  Consequently,  in  the  end  pieces  the 
grains  are  vertical. 

Grooves  are  cut  in  the  side  pieces  to  let  in  the  bottom  and  the  end 
pieces.  There  is  not  a  nail  nor  a  pin  used  for  holding  it  together.  It 
is  wholly  secured  by  square  iron  rods  with  nuts  and  screws,  resembling 
sleigh  rods,  with  broad  collars  to  prevent  their  sinking  into  the  wood, 
and  these  are  confined  to  the  two  side  pieces  Four  rods  at  each  end 
and  four  under  the  bottom  are  sufficient.  These  may  be  loosened  and 
tightened,  by  turning  the  nuts,  as  the  planks  swell  and  shrink.  A  lid  is 
attached  to  one  end  of  the  cistern  by  strong  iron  hinges.  This  is  very 
useful  for  covering  up  the  cistern  to  prevent  its  freezing  in  cold  weath- 
er, for  the  convenience  of  transportation,  and  to  serve  for  a  table  when 
open. 

The  inside  of  the  cistern  is  divided  into  two  parts,  by  inch  square 
posts,  screwed  to  the  side  pieces  within,  and  by  a  beam  an  inch  and  a 
half  in  depth  and  an  inch  thick  resting  upon,  and  screwed  to  the  upper 
ends  of  the  posts.  The  upper  side  of  the  beam  is  four  inches  lower 
than  the  top  of  the  cistern.  The  smallest  division  is  the  well,  and  is 
half  as  large  as  the  other  ;  across  which,  with  iis  ends  supported  on  the 
said  beam  and  abeam  at  the  end,  is  the  moveable  shelf.  This  is  three 
inches  wide  and  two  inches  thick,  having  two  invertedtunnels  wrought 
in  its  under  side,  terminating  upwards  in  small  holes  perforating  the 
shelf.  One  of  these  holes  is  about  three-fourths  of  an  inch  in  diameter, 
which  is  generally  used ;  the  other  is  a  quarter  of  an  inch  in  diameter, 
furnished  with  a  half-inch  tube  which  is  used  for  filling  vials  with  gases. 
Shoulders  are  cut  at  each  end  of  the  shelf,  letting  it  down  so  that  it  is 
but  half  an  inch  higher  than  the  top  of  the  beams  ;  to  prevent  its  rising 
up  it  is  loaded  with  lead. 

Common  wooden  water-pails,  with  wooden  hoops,  are  used  for  gas- 
holders. Pails  are  selected  of  a  size  and  height  fitted  to  the  size  and 
depth  of  the  cistern.  The  ears  nre  cut  off  and  one  side  of  the  top  cut 
in  a  little,  so  as  to  permit  water  to  enter,  when  they  are  inverted  on 
the  bottom  of  the  cistern  ;  for  they  are  always  used  with  their  bottoms 
upwards.  Each  pail  has  a  half-inch  and  quarter-inch  hole  in  its  bot- 
tom, for  the  admission  of  large  and  small  stop-cocks,  tubes,  &c.  These 
inverted  pails  may  be  held  down  in  the  water  by  cross-bars  let  into  the 
sides  of  the  cistern,  OK  by  a  board  cover.  Such  a  cover  may  equal  the 
size  of  all  the  surface  of  the  cistern  but  the  well,  and  form  a  level  with 
the  top  of  the  moveable  shelf  It  may  be  perforated  with  auger-holes 
for  admitting  the  necks  of  inverted  decanters.  Some  of  these  holes 
may  correspond  with  the  holes  in  the  pail  gasholder.  These  auger-holes 
are  very  convenient  when  decanters  are  used  for  collecting  and  hold- 
ing gases,  as  a  cheap  and  convenient  substitute  tor  bell-glasses. 

A  forge  and  furnace.  Let  a  sheet-iron  box  be  made,  12  inches  long, 
10  inches  wide  and  10  inches  high  Let  the-corners  be  as  nearly  square, 
as  the  sheet-iron  can  be  conveniently  wrought.  Let  a  hole  be  made 


8  PORTABLE   APPARATUS. 

in  one  end  about  an  inch  in  diameter,  3  inches  above  the  bottom,  for 
tlie  admission  of  a  bellows  pipe.  Place  the  neck  for  the  stove  pipe  on 
the  top,  very  near  the  opposite  end.  Cut  an  opening  for  a  door  in  the 
middle  of  one  side  of  the  stove,  nearly  of  a  semi-circular  form,  with  the 
strait  side  down,  3  inches  above  the  bottom.  Let  its  strait  side  be  6 
inches,  and  the  height  6  inches  Let  the  piece  so  cut  be  used  for  a  door 
or  lid,  by  shoving  it  up  one  inch,  and  supporting  it  at  that  height  by  2 
iron  pins  near  the  top  of  the  opening  on  the  outside,  and  two  corres- 
ponding holes  in  the  upper  edge  of  the  lid  to  suspend  it  by.  Cut  a  hole 
one  inch  and  a  half  in  diameter,  opposite  to  the  centre  of  the  base  of 
the  door,  2  inches  above  the  bottom  of  the  stove.  A  suitable  length  of 
pipe  for  conducting  off  the  smoke  under  the  mantle  piece  of  a  chimney 
or  out  at  a  window,  finishes  the  iron  part  of  the  forge,  which  can  always 
be  borrowed  for  a  course.  A  dripping  pan,  with  a  3  inch  brim,  as  largo 
as  can  be  put  into  the  door,  will  be  wanted  for  a  sand  bath.  To  use 
this  apparatus,  make  a  strong  bench,  about  three  feet  high,  and  a  few 
inches  wider  and  lorigei  than  the  box,  and  set  it  about  8  feet  back  of 
the  cistern.  Let  it  be  so  situated  that  every  auditor  can  see  an  experi- 
ment at  the  nose  of  the  bellows.  Cover  the  bench  with  brick,  and  set 
the  stove  upon  them.  Set  a  row  of  brick  edgewise  around  the  inside 
of  the  stove.  Bore  ajiole  through  two  brick  for  the  bellows  pipe  to  go 
through.  Then  lay  a  floor  of  one  thickness  of  brick  inside  of  the  stove, 
or  box. 

When  a  forge  is  wanted,  put  in  the  coal,  leaving  the  door  or  lid  off, 
and  proceed  as  with  other  forges.  When  a  sand  bath  is  wanted,  set  in 
the  dripping  pan  half  filled  with  sand,  supported  on  another  lining  of 
briek,  with  coal  filled  in.  The  heat  under  the  pan  may  be  regulated  by 
the  bellows  ;  or  the  lid  may  be  put  up  and  a  brick 'left  off  in  front, 
when  the  inch  opening  under  the  lid  will  operate  as  an  air  furnace.  It 
may  be  used  as  an  air  furnace  for  any  other  purposes  in  the  same  way. 
The  sheet  iron  sides  of  the  stove  may  be  as  easily  defended  with  the 
loose  brick,  as if  set  in  mortar.  Be  careful  to  keep  a  quantity  of  square- 
edged  brick,  squared  on  a  grindstone,  of  equal  dimensions. 

A  bellows.  A  large  hand  bellows  is  sufficient  for  any  experiments. 
It  may  be  fastened  to  a  moveable  stand  or  block,  so  that  it  will  lie 
down  steadily  when  used. 

Tongs  One  light  pair  of  tongs,  with  the  rivit  near  the  bows,  like 
taylors'  shears  ;  and  one  pair  fitted  both  to  hold  a  crucible  and  to  pinch 
a  small  thing  as  a  nail  are  sufficient. 

Crucibles.  Two  large  lead  pots,  with  perforated  bottoms,  having- 
tops  large  enough  to  take  in  a  pint  retort;  and  two  or  three  nests  of 
common  crucibles. 

Gun-barrels.  Two  gun-barrels  at  least,  perfectly  stopped  at  the 
brich,  and  air  tight,  will  be  wanted  ;  for  that  which  is  kept  for  oxygen 
must  not  be  used  for  carburetted  hydrogen,  nor  for  any  other  purpose, 
but  collecting  oxygen. 

Gas-tubes.  Two  leaden  tubes,  drawn  down  to  about  one  fourth  of 
an  inch  caliber,  long  enough  to  reach  from  a  gun-barrel  set  in  the  forge, 
to  half  across  the  cistern.  A  few  lead  and  glass  tubes  will  be  wanted 
of  various  sizes. 


PORTABLE   APPARATUS. 

Stop-cocks.  About  half  a  dozen  good  stop-cocks  will  be  necessary. 
Small  brass  cocks  at  the  hardware  stores  will  do,  if  no  better  can  be 
had,  by  filing  off  the  crooked  part. 

Flexible. tubes.  These  may  be  made  of  good  calf-skin.  Such  tubes 
will  not  hold  the  gases,  unless  they  are  soaked  in  water  three  or  four 
hours  before  they  are  used  ;  or  a  shorter  time  if  the  water  is  moder- 
ately warmed. 

Ladle  and  spoons.  A  common  iron  ladle,  which  will  hold  a  pint  or 
a  little  less.  A  common  iron  table  Spoon,  a  tea-spoon,  and  silver  mus- 
tard spoon,  very  small. 

Glass  ware.  6  pint  retorts,  6  half  pint  retorts,  2  half  gallon  bell- 
glasses,  2  quart  bell-glasses,  2  tubulated  quart  bell-classes,  6  assay 
glasses  without  feet  or  noses,  sometimes  called  glass-cylinders,  2  bolt- 
heads  or  rnattrasses  with  6  inch  necks,  1  air  thermometer,  made  like  a 
bolthead  only  more  slender  and  delicate,  a  dozen  test  glasses,  2  dozen 
8  ounce  vials,  1  dozen  plain  pint  and  1  dozen  quart,  decanters,  an  iron 
mortar,  and  a  pint  wedgewood  mortar. 

Borrowed  glass  ware,  crockery,  fyc.  Any  liberal  crockery  merchant 
and  druggist  will  lend  the  following  articles,  on  condition  they  are  paid 
for  or  returned  clean  and  sound.  3  dozen  plain  wine  glasses,  6  quart 
and  6  pint  tumblers,  6  large  and  6  small  white  earthen  plates,  2  plain 
pitchers,  6  quart  and  6  pint  earthen  bowls,  2  large  wash  bowls. 

Mercurial  trough.  Get  a  mercurial  trough  cut  in  a  block  of  wood 
about  9  inches  long  and  6  wide.  Let  it  be  cut  3  inches  deep,  6  inches 
long,  and  so  narrow  as  to  hold  12  Ib.  of  mercury,  and  leave  an  inch 
unfilled.  A  deep  groove,  for  laying  down  a  vial,  in  one  side  of  the- 
bottom.  A  druggist  will  lend  the  mercury,  if  the  deficiency  in  weight 
be  paid  for. 

Reflector.  A  plain  sheet  of  tin  for  a  reflector.  Also  a  ball  of  iron 
with  an  eye  to  hang  it  by,  for  using  with  the  reflector.  See  Caloric, 
Prop.  17. 

Scales.    An  accurate  pair  of  scales  with  grain  weights. 

Florence  flasks.     About  two  dozen. 

Bags.    About  a  dozen  bladders  for  bags,  large  and  small. 

Kettle.  A  sheet  iron  kettle,  holding  about  3  quarts,  with  a  handle  oa 
one  side  18  inches  long,  and  pouring  nose  on  another  side. 

Dripping  pan.  An  extra  dripping  pan,  besides  that  used  fora  sand 
bath,  and  about  12  inches  square,  for  holding  coals,  and  for  setting  the 
lead  pot  in.  This  may  be  set  on  a  couple  of  bricks  laid  on  a  table  or 
bench,  when  coals  are  put  in  the  pan,  or  when  the  lead  pot  contains 
coals  and  is  set  in  it. 

Jack-o'-lantern  basin,  for  making  phosphuFetted  hydrogen.  See 
Phosphorus,  Prop.  5. 

Etching  box.  A  box  of  tin  (lead  or  copper  is  better,)  two  inches 
square  and  two  inches  high,  open  and  perfectly  even  oa  the  top.  It 


10  USE  OF  APPARATUS, 

should  be  set  in  a  hole  in  the  centre  of  a  tin  plate,  so  that  cold  water 
may  be  poured  on  a  piece  of  glass  laid  over  its  top,  without  wetting 
the  coals  on  which  the  box  stands.  See  Fluorine,  Prop.  1. 

Gas-pistol,  for  exploding  gas,  as  directed  under  Hydrogen,  prop.  3. 

Fire  syringe.  A  syringe  of  lead,  pewter,  or  other  metal,  six  inches 
long  and  closed  at  the  end.  See  Caloric,  Prop.  2. 

Hammers,  files,  a  compass-saw,  a  block  of  wood  for  an  anvil,  wire 
of  various  sizes,  gallipots,  tobacco  pipe.s,  pincers,  corkscrews,  and  nuirr 
erou.s  other  small  articles  will  be  wanted ;  which  will  occur  to  any  in- 
structor without  particular  directions. 

USE  OF  APPARATUS. 

The  cistern. is  set  firmly  on  short  cross  benches,  elevated  sufficiently 
to  bring  the  top  of  it  to  the  instructor's  elbows  It  is  filled  quite  full 
of  water  A  tub  stands  under  it  with  one  edge  projecting  a  few  inches, 
directly  under  a  large  brass  cock,  which  is  fitted  in,  level  with  the'in- 
side  bottom  of  the  cistern.  A  long  horizontal  hole  or  slit  is  cut  against 
the  centre  of  the  well,  half  an  inch  thick.  A  stopper  is  fitted  to  this, 
which  maybe  pulled  out  to  let  the  water  run  through  it  into  the  tub, 
•when  the  experiments  are  of  that  kind  which  may  cause  the  cistern  to 
run  over. 

1.  Let  each  of  the  students  Jill  the  bell-glasses  with  icater  and  set  them 
on  the  shelves.    Hold  a  bell-glass,  tumbler,  cylinder,  or  specie  bottle,  in 
a  horizontal  position  over  the  well.     Sink  it  in  this  position  until  it  is 
almost  full,  lower  the  closed  end  until  all  .the  air  passes  out ;  then  turn 
the  closed  e<nd  upwards  and  raise  it  carefully,  pressing  it  against  the 
shelf  until  it  is  high  enough  to  slide  on  the  shelf. 

2.  Ltt  each  student  transfer  air  from  one  bi ll-glass  to  another. 

In  this  operation  let  the  air  be  carefully  poured  up  under  water,  into 
a  glass  filled  with  water  so  that  no  bubbles  shall  escape. 

3.  Let  each  student  pour  air  into  the  wooden  gas-holder. 

In  performing  this  operation,  slide  the  vessel  down  against  the  gas- 
holder, keeping  it  in  a  vertical  position  until  it  reaches  the  bottom  of 
the  cistern.  Then  incline  it  towards  the  horizontal  position,  and  at  the 
same  time  raise  the  gas-holder  ;  and  crowd  it  gradually  into  the  gas- 
holder. 

4.  Let  each  student  pass  a  current  of  air  from  a  gas-holder  by  way  of 
a  stop-cock  through  a  lead  tube. 

A  stop  cock  is  fitted  into  one  of  the  holes  of  a  gas-holder  (the  other 
hole  being  stopped  with  a  peg,)  and  the  gas-holder  is  afterwards  filled 
with  air  by  blowing  the  air  under  it  through  a  tube.  The  gas-holder 
being  filled,  press  it  down  to  the  bottom  of  the  cistern,  and  stay  it  there. 

Fix  a  lead  tube  to  the  stop-cock,  and  turn  the  stop.  A  strong  cur- 
rent will  be  forced  out  by  the  pressure  of  the  water  of  the  cistern  int' 
the  gas-holder  below. 


CHEMICAL   SUBSTANCES.  11 

5.  Let  each  student  pass  a  current  of  air  from  a  gas-holder  tfirougha 
flexible  tube  and  tobacco-pipe,  and  make  soap  bubbles. 

Perform  this  operation  as  directed  under  Hyd  Prop  7. 

6.  Let  each  student  Jill  a  small  glass  cylinder,  invert  it  and  set  it  on  tht 
shelf  of  the  mercurial  trough. 

This  operation  is  performed  as  directed  with  water.  But  requires 
that  the  glass  cylinder  be  grasped  firmly  and  held  steadily. 

7.  Let  each  student  use  a  retort  by  passing  a  common  gas  into  a  receiver. 
In  performing  this  experiment,  let  the  student  produce  hydrogen,  as 

directed  under  Hyd.  Prop.  1. 

8.  Let  each  student  take  the  specific  gravity  of  a  mineral. 

Weigh  a  small  mineral  specimen  in  the  air,  suspended  from  a  beam 
of  the  scales  by  a  fine  silk  thread.  Then  let  it  hang  in  a  tumbler  of 
water  and  weigh  it  there.  Now  subtract  the  weight  in  water  from  the 
weightinair,  and  divide  the  weight  in  the  air  by  the  difference,  and 
the  quotient  will  be  the  specific  gravity. 

CHEMICAL  SUBSTASSTCZSS, 

FOR    A    COURSE    OF    EXPERIMENTS. 

Tests  for  acids  and  alkalies.  Collect  in  the^nonth  of  October  or  No- 
vember, leaves  from  the  red  cabbage.  Those  of  the  brightest  red  are 
rot  the  best ;  but  those. should  be  selected,  which  are  rather  bluish  or 
glaucous.  Dry  the  thinnest  part  of  the  leaves,  or  the  bark  of  the  stalk, 
by  slow  heat  of  a  fire  or  stove.  The  heat  should  not  be  sufficient  to  dry 
them  in  less  than  four  or  five  days.  When  dried  sufficiently  break 
them  up  pretty  fine  by  rubbing  them  in  the  hands,  and  c-»rk  them  up  in 
dry  phials.  When  wanted  for  use  put  about  a  tea-spoonful  into  a  wine- 
glass of  pure  rain  or  river  water,  and  soak  it  about  an  hour.  Then 
press  it  with  a  rod  and  pour  off  the  water  into  another  wine-glass  or 
phial  for  use  It  should  never  be  used  after  the  infusion  has  been 
made  longer  than  two  or  three  days. 

Procure  at  the  shops,  or  elsewhere,  the  following  substances  for  one 
course  of  lectures. 

Sulphuric  acid  2  quarts,  nitric  acid  1  pint,  muriatic  acid  1  pint,  irom 
filings  at  the  gun  smith's  2  pounds,  phosphorus  1  ounce,  oxymuriate 
of  potash  1  ounce,  sulphur  1  roll,  sea  coal  3  pounds,  hard  soap  1  pound, 
chalk  2  pounds,  carbonate  of  ammonia  1  pound,  muriate  of  ammonia  4 
ounces,  oxyd  of  manganese  10  pounds,  saltpetre  1  pound,  red  lead  1 
pound,  prarl  ash  2  pounds,  quicklime  6  pounds,  fine  table  salt  2  quarts, 
white  wax  1  cake,  borax  2  ounces,  fluc>r  spar  6  ounces,  carbonate  of 
soda  3  ounces,  liquid  ammonia  8  ounces,  copperas  8  ounces, blue  vitriol 
2  ounces,  alum  2  ounces,  white  vitriol  1  ouncf,  magnesia  of  the  shops 
2  ounces,  epsom  salts  6  ounces,  sugar  of  lead  2  ounces,  corrosive  sub- 
limate 1  ounce,  calomel  1  ounce,  lunar  caustic  quarter  of  an  ounce, 
verdigris  2  ounces,  nut  galls  2,  prussiate  of  potash  quarter  of  an  ounce, 
spirits  of  turpentine  1  pint,  oxalic  acid  quarter  of  an  ounce,  or  it  may 
be  obtained  in  the  expressed  juice  of  green  wood-sorrel,  alcohol  1  pint, 
ether  1  ounce.  A  little  zinc,  tin  foil  and  grain  tin,  bismuth,  gold  leaf, 


12 


COURSE  OF  LECTURES. 


arsenic,  copper  filings  and  lead.  Also  a  little  gum-arabic,  starch, 
white  sugar,  sweet  oil,  rosin,  camphor,  liquorice  in  ball,  iridia  rubber, 
indigo,  prussian  blue,  flowers  of  bt-nzoin,  citric  acid,  vinegar,  glue, 
isinglass,  iodine,  sulphuric  ether,  nitrate  or  muriate  of  barytes  and 
strontian,  chromate  of  potash,  zaffre,  silver  leaf,  plat ina  wire,  best  pot- 
ter's clay,  tobacco  pipes,  a  coil  of  wax  tapers,  common  potash,  a  pound 
of  tow,  3  pounds  of  putty  for  lutes,  gun  flints,  3  sizes  of  iron  and  brass 
wire. 

It  is  best  to  put  all  these  articles  into  phials,  boxes,  and  paper  bag?, 
«hut  closely ;  and  have  them  all  labelled  and  well  arranged. 

COURSE  OF  XiXSCTUlLES. 

Divide  the  course  into  thirty  lectures.  Each  lecture  should  occupy 
one  hour.  If  a  very  full  course  is  required,  one  hour  and  forty  min- 
utes. If  a  hasty  illustration  of  general  principles  is  required,  half  an 
.hour  to  a  lecture  is  sufficient,  and  two  half  hour  lectures  may  be  given 
each  day.  Let  the  subject  of  each  lecture  be  as  follows  : 


1st  lecture  to  include  Affinity. 

2d,  first  half  of  Caloric. 

3d,  last  half  of  Caloric. 

4th,  Electricity  and  Light. 

5th,  Oxygen,  and  the  Nomencla- 
ture. 

6th,  Chlorin  gas. 

7lh,  Muriatic  acid,  Fluorin,  and 
lodiri. 

Qlh,  first  half  of  Hydrogen. 

9th,  last  half  of  Hydrogen. 
I0th,  first  half  of  Nitrogen, 
llth,  last  half  of  Nitrogen. 
12th,  Sulphur. 
13th,  Phosphorus. 
14th,  first  half  of  Carbon. 
15th,  last  half  of  Carbon,&.  Boron 
36th,  Potash,  and  the  Nomencla- 
ture. 
I7tb,  Soda  and  Ammonia. 


18th,  Lime. 

59th,  Barytes,  Strontian,  Magne- 
sia and  Silex. 

20th,  Alumine,  and  Metals  in  gen- 
eral 

21st,  Iron,  Manganese  and  Tin. 

22d,  Zinc,  Arsenic  and  Chrome. 

23d,  Copper,  Antimony,  Bismuth 
and  Cobalt.. 

24th,  Gold,  Silver  and  Platina. 

25th,  Mercury,  Lead,  and  Nickel. 

26lh,  Vegetable  Substances 

27th,  Animal  Substances  and  Dy- 
ing. 

28th,  Analysis  of  Mineral  Waters 
and  Soils. 

29th,  first  half  of  Analysis  of  Min- 
erals 

30th,  last  half  of  Analysis  of  Min- 
erals. 


13 
OX.  &S3XFIC  ATXONT 

OF 


IN  the  present  state  of  chemical  science,  it  is 
supposed  that  we  have  fifty-six  chemical  princi- 
ples ;  and  that  each  of  these  principles,  excepting 
affinity,  is  a  simple  material  substance,  differing 
in  some  essential  qualities  from  all  the  others. — • 
Eighteen  of  these  are  either  very  uncommon  or  of 
a  douhtful  nature,  or  unmanageable  in  the  arts. 
Only  thirty -seven  of  the  simple  substances  are 
used  in  the  arts  or  in  agriculture.  As  all  animal 
and  vegetable  matter,  all  soils,  all  works  of  art, 
and  every  thing  with  which  we  are  concerned  in 
life,  consist  of  one,  two,  or  more  of  the  thirty- 
seven  simple  substances,  which  are  printed  in 
italics  in  the  following  list,  they  may  be  consid- 
ered as  the  chief  subjects  for  the  attention  of  the 
student  in  chemistry 

Chemical  principles  are  distributed  into  five 
classes. 

CLASS  i.  ,  POWERS. 
*  Affinity,  Caloric,  Electricity,  Light. 

CLASS  2.     ACIDIFYING  SUBSTANCES. 
Oxygen,  f  Chlorine  ?  Fluorine?  Iodine? 

*  This  is  an  universal  property  of  matter. 

\  *  do  not  believe,  that  either  of  these  three  last  is  a  simple  or  acid- 
ifying substance.  But  I  am  compelled  to  submit  to  the  force  of  au- 
thority. 


14  CLASSIFICATION. 

CLASS  3.      OXYDABLE   SUBSTANCES,  NOT  ME- 
TALLIC. 

Hydrogen,  Nitrogen,  Sulphur,  Phosphorus  $ 
Carbon,  Boron,  Selenium. 

CLASS  4.     METALLOIDS. 

Section  1.  The  bases  of  alkalies  and  of  alka- 
line earths.  Of  Potash,  of  Soda,  of  Lime,  of 
Barytes,  of  Strontian,  of  Magnesia,  of  Lithia. 

Section  2.  The  imaginary  bases  of  non-alka- 
line earths.  Of  Silex,  of  Jllumine,  of  Glycine, 
of  Zircon,  of  Yttria,  of  Thorina. 

CLASS  5.     METALS. 

Section  1.  Those  which  absorb  oxygen  with 
such  force  as  to  decompose  water  when  heated 
sufficiently.  Iron,  Manganese,  Tin,  Zinc,  Cad- 
mium. 

Section  2.  Those  which  absorb  oxygen,  but 
not  with  sufficient  force  to  decompose  water,  and 
from  which  oxygen  cannot  be  separated  by  heat 
alone.  (Some  are  capable  of  becoming  acids.) 
Arsenic,  Chrome,  Molybdena,  Tungsten,  Colum- 
bium.  (Others  are  not  capable  of  becoming  acids.) 
Copper,  Antimony,  Bismuth,  Cobalt,  Titanium, 
Tellurium,  Cerium,  Uranium. 

Section  3.  Those  which  receive  oxygen  artifi- 
cially from  the  decomposition  of  strong  acids  only. 
Gold,  Silver,  Platina,  Palladium,  Osmium,  Rho- 
dium, Iridium. 

Section  4.  Those  which  absorb  oxygen  at 
limited  temperatures,  and  give  it  wholly  off  at 
higher  temperatures.  Mercury,  Lead,  Nickel. 


CLASSIFICATION.  l5 

ORGANIC  SUBSTANCES. 

All  vegetable  and  animal  bodies  have  for  their 
ultimate  elements  three  or  more  of  the  preceding 
simple  substances.  Carbon,  oxygen  and  hydro- 
gen are  essential  to  vegetable  matter.  Carbon, 
oxygen,  hydrogen  and  nitrogen,  are  essential  to 
animal  matter.  Other  simple  elements  are,  in  al- 
most all  cases,  combined  with  these. 

PROXIMATE    ELEMENTS. 

Those  substances  which  are  produced  in  plants 
and  animals  by  the  common  operations  of  nature, 
are  denominated  proximate  principles,  or  proxi- 
mate elements. 

Of  Plants.  Gum,  resin,  gum-resin,  fixed  oil> 
volatile  oil,starch,  gluten,albumen,  fibrin,  gelatine, 
bitter  principle,  extractive  matter,  tannin,  wax, 
camphor,  sugar,  guaiacum,  balsam,  caoutchouc, 
indigo.  These  are  the  most  important.  Several 
others  are  described  in  authors  ;  besides  the  ve- 
getable acids,  which  will  be  noticed  hereafter. 

Of  Animals.  Gelatine,  albumen,  fibrin,  gase- 
ous matter,  &c.  which  will  also  be  described  here- 
after. 

All  compounds  in  the  mineral  kingdom,  as  am- 
ber, bitumen,  &c.  and  ail  *the  aerological  com- 
pounds, as  the  atmosphere,  and  the  various  va- 
pours and  compound  gases  which  float  in  it,  and 
all  other  material  compounds  of  which  we  have 
any  knowledge,  consist  wholly  of  a  greater  or 
less  number  of  the  chemical  principles  enumerat- 
ed in  the  five  classes. 


16  CLASS    I.       POWERS. 

CLASSES  OF  CHEMICAL  PRINCIPLES. 

CLASS  I.     POWERS. 

PRINCIPLE    1.       AFFINITY. 

Natural  History  and  general  Remarks. 

The  term  Natural  History  is  considerably  dis- 
torted in  applying  it  to  this  class  of  chemical  prin- 
ciples. This  liberty  is  taken  here  for  the  sake  of 
uniformity. 

Affinity  is  an  universal  property  of  matter  ; 
consequently  it  is  in  all  places  where  matter  is 
found.  Though  the  other  three  powers  are  sup- 
posed to  be  matter  by  most  chemists,  affinity  is 
not  held  to  be  so  by  any.  It  is  one  of  the  five 
kinds,  or,  as  some  express  it,  one  of  the  five  modi- 
fications of  attraction.  The  other  four,  viz.  of 
cohesion  or  adhesion,  of  gravitation  or  electricity, 
and  of  magnetism,  appertain  to  the  department  of 
Natural  Philosophy.  Being  the  only  kind  of  at- 
traction which  is  employed  as  an  efficient  agent 
or  power  in  producing  chemical  changes,  it  is 
called  chemical  attraction. 

The  term  affinity  is  limited  exclusively  to  hete- 
rogeneous attraction  ;  that  is,  when  dissimilar  par- 
ticles or  atoms  are  compounded  together.  Homo- 
geneous attraction,  or  that  application  of  attrac- 
tion, whereby  similar  particles  are  held  together, 
as  the  constituent  particles  of  a  bar  of  wrought 
iron,  should  be  placed  under  cohesive  attraction. 

Affinity  is  simple  or  elective  in  its  effects,  ac- 
cording to  its  applications  ;  though  the  principle 
is  a  single  one  and  uniform  in  its  operations. 

Proposition  1.  Simple  affinity  is  that  applica- 
tion of  affinity  or  chemical  attraction,  whereby  the 


PRINCIPLE  1.       AFFINITY.  17 

constituent  atoms  of  a  compound  body  are  united, 
without  causing  any  decomposition. 

Illustration.  Pour  a  teaspoon  of  olive  oil  into 
half  a  wine  glass  of  water.  No  combination  will 
take  place.  Drop  in  a  piece  of  pearlash,  half  the 
size  of  a  pigeon's  egg,  let  it  dissolve  and  stir  the 
mixture,  which  will  effect  a  chemical  combination, 
and  produce  white  soap. 

Rationale.  Water  and  oil  repel  each  other  ; 
therefore  these  two  substances,  on  being  mixed, 
illustrate  the  absence  of  affinity.  All  alkalies 
(of  which  potash,  the  basis  of  pearlash,  is  one) 
attract  both  water  and  oil'.  Consequently  it  ope- 
rates as  tlie  bond  of  union  between  the  water  and 
oil.  While  this  union  is  effected  nothing  is  ex- 
cluded. No  decomposition  having  taken  place, 
the  experiment  has  been  performed  by  simple  af- 
finity. 

Application.  By  the  application  of  this  princi- 
ple, soft  soap  is  manufactured  with  oil  (or  soap- 
grease)  potash  and  water — Hard  soap  with  oil, 
soda  and  water.  Also  volatile  liniment  with  am- 
monia, olive  oil  and  water.  Sulphuric  acid  (oil 
of  vitriol)  by  the  direct  combination  of  sulphur 
and  oxygen. 

Elective  affinity  is  either  single  or  double. 

Prop.  2.  Single  elective  affinity  is  that  appli- 
cation of  affinity,  whereby  the  constituent  atoms  of 
a  new  compound,  by  the  force  of  their  attraction, 
exclude  others  from  a  previous  state  of  combina- 
tion.1 

Illustration.  Put  a  teaspoon  of  table  salt  into 
a  win*  glass,  which  had  been  previously  dried  on 
a  plate.  Pour  upon  it  a  teaspoon  of  sulphuric 

2* 


18  CLASS    I.       POWERS, 

acid.  Muriatic  acid  gas  will  escape  into  the  at- 
mosphere, and  Glauber's  salts  will  be  formed  in 
the  wine  glass. 

Rationale.  Table  salt  consists  of  muriatic  acid 
and  soda.  Soda  has  a  stronger  affinity  for  sul- 
phuric acid  than  for  muriatic.  It  therefore  elects 
the  sulphuric  acid,  and  unites  with  it  with  such 
force,  as  to  exclude  the  muriatic.  Such  is  the  na- 
ture of  the  muriatic  acid  that  when  separated  from 
its  combination  with  other  substances,  it  becomes 
a  gas  and  enters  into  the  atmosphere.  It  is  in- 
visible, but  by  its  attraction  for  water  it  unites  to- 
gether, or  condenses,  the  aqueous  vapour  of  the 
atmosphere  so  as  to  render  the  vapotir  visible. 
By  the  visibility  of  the  vapour  we  perceive  the 
course  and  motions  of  the  gas. 

Application.  On  this  principle  soda  is  obtain- 
ed from  common  salt  for  the  manufacture  of  coarse 
hard  soap.  The  muriatic  acid  of  the  salt  elects 
the  potash  which  is  introduced,  and  the  soda  of 
the  salt  being  excluded,  immediately  unites  to  the 
animal  oil  and  forms  with  it  the  hard  soap.  See 
this  process  more  fully  explained  under  soda. 

Prop.  3.  Double  elective  affinity  is  that  appli- 
cation of  affinity  whereby  neutral  compounds  de- 
compose each  other  and  form  other  neutral  com- 
pounds. 

Illustration.  Take  about  four  parts  of  muriate 
of  lime  and  five  parts  of  sulphate  of  soda,  weigh- 
ing them  after  being  well  dried  over  coals  on. 
plates  Dissolve  them  in  water  separately.  Now 
mix  them  in  a  wine  glass,  and  a  precipitate  of  sul- 
phate of  lime  (gypsum)  will  soon  settle  at  the  bot- 
tom, and  a  solution  of  muriate  of  soda  will  stand 
over  it.  On  testing  the  new  compounds  with  red 


PRINCIPLE    1.       AFFINITY.  19 

cabbage,  they  will  be  found  to  be  neutral  salts — 
exhibiting  neither  the  acid  nor  alkaline  test.  On 
tasting  the  liquid  it  will  be  found  to  be  a  solution 
of  table  salt. 

If  the  proportions  of  sulphate  of  soda  and  mu- 
riate of  lime  are  mixed  at  random,  after  being  dis- 
solved, without  weighing  or  measuring,  the  result 
will  be  pretty  satisfactory,  provided  the  muriate 
of  lime  be  in  excess.  Sulphate  of  lime  will  be 
precipitated,  and  the  supernatant  liquid  will  be  a 
mixture  of  muriate  of  lime  and  muriate  of  soda. 
The  muriate  of  lime  being  almost  tasteless,  the 
new  formed  muriate  of  soda  will  be  readily  recog- 
nized. 

Rationale.  Though  the  sulphuric  acid  and 
muriatic  acid  both  have  a  stronger  affinity  for  the 
soda  than  for  the  lime,  and  though  the  soda  has  a 
stronger  affinity  for  the  sulphuric  than  for  the  mu- 
riatic ;  yet  the  attraction  between  the  lime  and  the 
muriatic  acid  being  comparatively  feehle,  and  pret- 
ty strong  between  the  sulphuric  acid  and  the  lime, 
and  between  the  muriatic  acid  and  the  soda,  the 
sulphuric  acid  being  hard  pressed  by  the  effort 
made  by  the  muriatic  acid  and  soda  to  unite,  is 
drawn  away  by  the  lime  from  the  soda,  leaving 
the  muriatic  acid  in  possession. 

Application.  Corrosive  sublimate  of  the  shops 
is  made  upon  this  principle  by  sulphate  of  mercu- 
ry and  muriate  of  soda,  as  will  be  shown  under 
mercury.  Numerous  other  operations  will  be  re- 
ferred to  this  principle  under  the  various  bases  of 
numerous  compounds.  Upon  this  law  Dr.  Wol- 
laston  constructed  a  scale  of  chemical  equiv- 
alents, by  which  the  artist  or  the  chemist  can  at 
sight  determine  what  proportions  of  any  com- 


20  CLASS    I.       POWERS, 

pounds  are  required  for  decomposing  each  other 
without  loss.  For  if  the  proportions  be  found, 
between  the  quantities  of  the  bases  necessary  for 
saturating  any  one  acid,  the  same  relative  propor- 
tions of  the  same  substances  will  be  required  for 
saturating  all  other  acids.  Or  if  the  proportional 
quantities  of  acids  required  for  any  one  base  be 
determined,  the  same  relative  proportions  ojf  acids 
will  be  required  for  all  other  bases.  These  rela- 
tive proportions  of  acids  or  alkalies,  are  denomi- 
nated equivalents  to  each  other.  For  example  ; 
if  a  given  quantity  of  sulphuric  acid  should  re- 
quire for  saturation  three  times  as  much  potash  as 
aluinine,  then  it  would  follow  of  course  that  nitric 
acid  and  muriatic  acid  would  require  three  times 
as  much  potash  as  alumine  for  saturation  ;  though 
all  tin  se  acids  would  differ  from  each  other  in  the 
absolute  quantity  required. 

Prop.  4.  By  affinity  the  constituents  of  com- 
pounds are  united  in  definite  proportions,  in  all 
cases  wherein  the  properties  and  sensible  quali- 
ties are  thereby  changed, 

Illustration.  Put  into  two  wine  glasses  half  a 
teaspoon  of  muriatic  acid  to  each,  Put  a  solid 
ma^s  of  carbonate  of  soda  into  each,  of  equal 
weight,  and  in  such  quantity  as  to  be  beyond  what 
is  sufficient  to  saturate  the  acid.  After  efferves- 
cence ceases  weigh  what  remains  of  each  parcel 
and  they  will  be  found  to  be  equal.  Pass  about 
the  liquids  in  the  two  wine  glasses,  with  tasting 
rods  (pine  sticks  areas  good"  as  glass  rods)  and 
the  taste  of  common  table  salt  will  be  recognized 
by  all. 

Rationale.  The  soda  of  carbonate  of  soda  has 
a  stronger  affinity  for  muriatic  aciu  than  for  the 


PRINCIPLE    1.       AFFINITY.  21 

carbonic  ;  consequently  it  unites  to  the  muriatic 
acid  and  forms  common  table  salt,  (muriate  of  so- 
da.) The  effervescence  is  caused  by  the  escape 
of  the  carbonic  acid,  which  was  a  constituent  of 
the  carboaate  of  soda.  This  unit-n  of  the  soda 
with  the  portions  of  muriatic  acid  would  continue 
an  unlimited  time,  were  it  not  for  the  law  of  defin- 
ite proportions.  That  the  proportions  are  definite 
is  manifest  from  the  fact,  that  in  both  trials  the 
same  quantity  of  soda  is  required  for  the  same 
quantity  of  acid.  At  this  definite  point,  the  caus- 
tic alkali  (soda)  and  the  severe  acid,  (muriatic) 
become  common  table  salt. 

Application.  The  law  of  definite  proportions 
is  of  great  importance  in  the  arts.  It  regulates 
the  uniformity  of  compound  bodies,  and  prevents 
the  evils  which  migtt  arise  from  carelessness  or 
mistake  in  the  manufacture  of  many  articles.  la 
the  manufacture  of  copperas  for  example,  36  parts 
of  the  protoxyd  of  iron  will  unite  with  precisely 
40  parts  of  sulphuric  acid.  Ai  d  in  the  manufac- 
ture of  white  vitriol,  42  parts  of  oxyd  of  zinc  will 
unite  with  40  parts  of  sulphuric  acid.  These  are 
the  uniform  proportions  in  the  dry  state  ;  and  each 
takes  63  parts  of  water  for  crystallization.  There- 
fore if  the  manufacturer  should  carelessly  add  too 
much  acid  or  too  much  metal,  he  would  suffer  a 
loss  of  the  material  in  excess,  but  nature  would 
impose  this  law  upon  him  and  compel  him  to  give 
us  copperas  in  the  one  case  and  white  vitriol  in 
the  other,  notwithstanding  his  errors. 

Prop.  5.  By  affinity  some  substances  unite 
with  other  substances  in  several  definite  propor~ 
tions,  which  proportions  can  always  be  expressed 
in  whole  numbers  without  any  fractional  remain* 
der. 


22  CLASS    I.       POWERS. 

Illustration.  [This  experiment  cannot  be  giv- 
en during  a  lecture  before  a  class.]  Take  any 
quantity  of  nitric  acid,  and,  by  a  process  to  be 
given  under  nitrogen,  reduce  it  down,  by  taking 
away  portions  of  oxygen,  to  nitrous  acid,  hyponi- 
trous  acid,  deujoxyd  of  nitrogen  (nitric  oxyd  j  and 
protoxyd  of  nitrogen  (nitrous  oxyd,  or  exhilarat- 
ing gas)  and  the  proportions  of  oxygen  combined 
with  nitrogen  in  each  state  of  combination  will  be 
found  thus — In  the  protoxyd  of  nitrogen  175 
grains  of  nitrogen  will  be  combined  with  100  grains 
of  oxygen — in  deutoxyd  of  nitrogen  175  grains  of 
nitrogen  with  200  of  oxygen — in  the  hyponitrous 
acid  175  grains  of  nitrogen  with  300  of  oxygen — 
in  the  nitrous  acid  175  grains  of  nitrogen  with  400 
of  oxygen — in  the  nitric  acid  175  grains  of  nitro- 
gen with  500  of  oxygen. 

Rationale.  Nature  having,  in  the  case  of  the 
nitric  acid  of  saltpetre  combined  with  nitrogen  the 
highest  proportion  of  oxygon  which  it  will  receive^ 
and  it  being  extremely  difficult  to  combine  nitro- 
gen and  oxygen  chemically,  it  is  necessary  to  be- 
gin with  this  high  combination  and  reduce  the 
oxygen  down  to  its  lowest  proportion.  Then  on 
retracing  our  steps,  we  find  the  proportions  rising 
in  a  numeric  ratio.  The  same  rule  has  been 
found  to  govern  in  all  combinations  where  suffi- 
cient investigation  has  been  made. 

Application.  The  ATOMIC  THEORY  is  founded 
upon  the  above  fact.  Mr.  Dalton  infers,  and  sup- 
ports his  inference  with  great  ability,  that  the  ul- 
timate atoms  of  these  compounds  are  numerically 
combined.  For  example,  that  if  the  ultimate 
atom  of  oxygen  is  supposed  to  weigh  one,  the  ul- 
timate atom  of  nitrogen  weighs  one  and  three 


PRINCIPLE    1.       AFFINITY.  23 

fourths.  Then  one  atom  of  nitrogen  and  one  atom 
of  oxygen,  form  the  smallest  particle  of  the  pro- 
toxyd  of  nitrogen  (exhilarating  gas) — that  one 
atom  of  nitrogen  joined  to  two  atoms  of  oxygen 
form  the  smallest  particle  of  the  deutoxyd  of  ni- 
trogen— one  atom  of  nitrogen  to  three  of  oxygen 
form  the  hypbmtrpus  acid — one  atom  of  nitrogen 
to  four  of  oxygen  form  the  nitrous  acid — one  of 
nitrogen  to  five  of  oxygen  form  the  nitric  acid 
(aqua  fortis.)  See  JVPNevin's  Atomic  Theory — 
also  Thompson,  Brande,  Ure,  and  Gorham. 

Prop.  6.  B?j  affinity  some  substances  unite  in 
indefinite  proportions,  and  their  properties  and 
sensible  qualities  are  not  changed. 

Illustration.  Mix  alcohol  and  water,  or  sul- 
phuric acid  and  water.  The  qualities  and  sen- 
sible properties  of  both  these  liquids  will  remain 
unchanged.  Being  diffused  among  the  water, 
there  will  be  less  of  them  in  a  given  measure  or 
space,  but  they  will  remain  unchanged. 

Rationale.  The  combination  is  not  a  mere  me- 
chanical suspension  like  clay  diffused  in  water, 
because  they  will  never  settle  down  at  the  bottom 
of  the  water.  It  must  therefore  be  a  chemical 
compound  ;  though  very  different  from  that  des- 
cribed in  the  4th  proposition. 

Application.  Proof  spirit,  brandy,  gin,  &c.  are 
made  by  combining  alcohol  with  water.  If  more 
water  is  added,  as  in  forming  what  is  called  grog, 
still  the  alcohol  is  not  changed.  Caloric  unites 
with  ice,  forming  water,  and  with  water  forming 
steam,  without  changing  the  nature  of  the  water. 
But  the  proportion  is  definite  for  changing  ice  to 
water  and  water  to  steam  5  and  here  the  change 


24  CLASS    I.       POWERS. 

of  the  state  of  it  seems  to  bear  a  suitable  propor- 
tion to  the  definite  proportion  of  caloric. 

Prop.  7.  Heat  increases  the  strength  of  chem- 
ical affinity.  v 

Illustration.  Pour  cold  nitric  acid,  diluted  with 
about  an  equal  measure  of  water,  upon  lead  shav- 
ings in  a  florence  flask,  and  little  or  no  action  v\  ill 
take  place.  Set  the  flask  containing  the  It  ad  and 
acid  upon  hot  coals,  or  over  a  candle  or  lamp,  ac- 
tion will  commence,  exhibiting  the  orange  fumes 
of  nitrous  acid,  &c. 

Rationale.  Lead  attracts  the  oxygen  of  the  ni- 
tyic  acid  very  feebly  when  cold.  When  heated 
its  attraction  encreasesin  strength,  and  it  takes  so 
much  oxygen  from  the  nitric  acid,  that  the  acid  is 
reduced  which  comes  in  contact  with  the  lead, 
producing  the  orange  gas.  The  process  of  reduc- 
ing nitric  acid  is  fully  explained  under  nitric  acid 
and  nitrous  acid. 

Application.  This  principle  has  an  almost 
perpetual  application  in  the  manipulations  of  the 
laboratory,  and  in  many  of  the  arts.  In  the  manu- 
facture of  soap,  though  it  may  be  made  cold,  the 
encreased  affinities  by  the  aid  of  heat,  greatly  ex- 
pedite the  combination  of  the  oil  and  alkalies.  In 
the  manufacture  of  sulphuric  acid,  the  affinity  be- 
tween sulphur  and  oxygen  is  never  sufficient  with- 
out the  aid  of  heat. 

Remark.  In  some  cases  elective  affinity  is  con- 
siderably varied  by  varying  the  proportion  of  the 
masses  of  substances  presented  to  each  other.— 
That  is,  the  weaker  affinity  may  be  strengthened 
by  increasing  the  quantity  of  the  substance  pos- 
sessing the  weaker  affinity.  This  complicated 


PRINCIPLE    2.       CALORIC.  25 

subject  is  ably  treated  by  Bertbollet  in  his  re 
searches  into  the  laws  of  chemical  affinity.     Also 
see  Gorhanrs  article  Affinity. 

Prop.  8.  In  some  cases  affinity  is  strengthened 
between  two  bodies  by  combining  one  of  them  with 
some  other  body. 

Illustration.  Put  copper  filings  into  a  vial  of 
pure  oxygen  gas,  and  they  will  not  unite.  Put 
them  into  a  wine  glass  of  nitric  acid,  and  they  will 
immediately  become  oxy  dated. 

Rationale.  Though  pure  oxygen  will  not  com 
bine  with  copper,  a  proportion  of  it  will  separate 
from  its  combination  with  nitrogen  in  the  nitric 
acid,  and  unite  with  the  copper  ;  thereby  reducing 
nitric  acid  to  nitrous  acid,  called  the  orange  gas. 
This  gas  will  be  seen  ascending  from  the  wine 
glass. 

Application.  In  the  manufacture  of  hard  soap, 
which  consists  of  animal  or  vegetable  oil  and  soda, 
the  two  substances  will  not  unite  without  boiling 
together  a  long  time.  But  if  the  manufacturer  first 
unites  the  oil  with  potash,  and  then  introduces 
muriate  of  soda  ;  when  the  potash  separates"  from, 
the  oil  to  unite  with  the  muriatic  acid,  the  soda,  of 
the  muriate  of  soda,  unites  almost  instantaneously 
with  the  oil. 

PRINCIPLE  2.     CALORIC. 
Natural  History  and  general  Remarks. 

Caloric  is  contained  in  every  body  constituting 
the  earth,  and  whatever  exists  upon  and  near  its 
surface.  It  is  probably  diffused  throughout  the 
solar  system,  and  even  throughout  the  universe. 
The  coldest  ice,  the  hardest  metal,  as  well  as  the 

3 


26  CLASS    I.      POWERS. 

most  expanded  gas,  all  contain  caloric  in  combi- 
nation. Steam  contains  caloric.  Abstract  caloric 
until  but  212  degrees,  according  to  Fahrenheit's 
scale,  remain,  and  it  will  become  water.  Take 
away  180  degrees  more,  leaving  but  32,  and  it 
will  become  ice.  Continue  to  abstract  more  and 
more,  until  the  known  powers  of  nature  and  of  art 
are  exhausted  in  the  operation,  and  there  will  still 
remain  an  immeasurable  proportion  of  caloric  in 
combination  with  the  ice. 

All  gases  and  liquids  would  become  solids,  if 
caloric  were  abstracted  to  a  certain  degree.  At- 
mospheric air  would  first  become  liquid,  liquids 
would  become  solids,  till,  at  length,  all  things 
would  become  as  permanently  solid  as  the  oldest 
primitive  rocks.  But  on  increasing  the  quantity 
of  caloric  in  the  whole  terrestrial  system,  all  sol- 
ids would  become  liquids,  and  liquids  would  be- 
come gases.  Rocks  would  become  fused,  and  at 
length  be  converted  into  gases.  By  continually 
adding  caloric,  the  whole  substance  of  the  earth 
and  its  inhabitants,  would  become  a  vast  globe  of 
rarified  gas.  Hence  it  follows,  that  all  substan- 
ces are  capable  of  being  in  the  state  of  a  solid,  of 
a  liquid,  or  of  a  gas  ;  and  that  these  states  depend 
on  the  quantity  of  caloric  held  in  combination. 
See  Lavoisier's  Elements. 

Proposition  1.  Caloric  and  light  are  not  the 
same  substance. 

Illustration.  Suspend  an  iron  ball,  which  is  at 
a  high  rt-d  heat,  by  a  wire,  opposite  to  a  sheet  of 
white  paper  pinned  to  the  wall,  and  at  the  dis- 
tance of  about  four  feet  from  it.  Place  an  air 
thermometer  between  the  ball  and  the  paper,  five 
OF  six  inches  from  the  paper.  After  the  liquid  in 


PRINCIPLE   2.       CALORIC.  27 

j 

the  thermometer  has  been  moved  down  by  the 
heated  ball  as  much  as  the  heat  will  move  it,  dark- 
en the  room.  Now  bring  a  pane  of  clear  glass 
before  the  ball,  at  the  distance  of  about  six  inches 
from  it.  The  liquid  in  the  thermometer  will  im- 
mediately rise,  while  the  light  thrown  upon  the 
paper  will  not  be  materially  diminished  by  the  in- 
terposition of  the  glass. 

Rationale.  Caloric  and  light  are  both  radiated 
from  the  heated  ball.  The  thermometer  is  affect 
ed  by  the  caloric,  and  the  paper  is  illuminated  by 
the  light.  If  light  and  heat  are  the  same  sub- 
stance both  should  be  equally  interrupted  by  the 
interposed  glass.  But  since  the  heat  is  greatly 
interrupted,  and  the  light  not  materially  inter- 
rupted (unless  it  be  by  some  imperfection  in  the 
glass,)  it  follows,  that  they  possess  different  prop- 
erties, and  cannot  be  the  same  substance. 

Application.  A  glass  screen  will  defend  the 
face  and  eyes  from  heat,  when  we  inspect  iron  or 
other  metal  in  a  state  of  fusion  with  a  magnifier 
of  two  or  three  inches  focus. 

Prop.  2.      Combined  caloric,  which  does  not 
excite  the  sensation  of  heat  nor  affect  the  ther- 
mometer, may  be  brought  to  the  free  stdte  by  com 
2?ression. 

Illustration.  Put  a  piece  of  tinder  in  the  end 
of  the  piston  of  the  fire  syringe,  consisting  of  cot- 
ton cloth  dipped  in  a  solution  of  saltpetre  and  well 
dried.  Force  down  the  piston  suddenly,  and  the 
tinder  will  take  fire. 

Rationale.  Caloric  was  combined  with  the  ah 
in  the  syringe  before  it  was  compressed  ;  in  which 
state  it  did  not  excite  the  sensation  of  heat  nor  in- 


IS  CLASS    I.       POWERS. 

flame  the  tinder.  When  it  was  compressed  by 
the  piston,  the  particles  of  air  were  brought  too 
near  each  other  to  afford  room  for  so  much  caloric. 
Part  of  it  being  forced  from  its  state  of  combina- 
tion, became  free  and  inflamed  the  tinder. 

Application.  There  is  so  much  caloric  in  the 
combination  with  air,  water,  and  other  substances 
about  us,  that  if  it  were  capable  of  producing  the 
ordinary  effects  of  heat,  the  whole  race  of  man 
Avould  be  burned  to  cinder  in  a  day.* 

Prop.  3.  Combined  caloric  may  be  brought  to 
the  free  state  by  mixing  liquids  which  strongly  at  - 
tract  each  other. 

Illustration.  Set  a  wine  glass,  half  filled  with 
cold  water,  within  about  half  an  inch  of  the  bulb 
of  an  air  thermometer.  Set  another  wine  glass 
equally  near,  half  filled  with  cold  sulphuric  acid. 
Let  them  stand  a  few  minutes.  Now  empty  the 
glass  of  sulphuric  acid  into  the  water,  and  the  air 
in  the  thermometer  will  be  considerably  expanded. 

Rationale.  In  this  experiment,  the  caloric  re- 
mains combined  with  both  liquids  while  they  are 
separate ;  and  the  thermometer  is  not  affected. 
But  when  they  are  mixed,  the  affinity  between 
sulphuric  acid  and  water  unites  them  so  closely  as 
to  diminish  their  bulk,  and  to  force  part  of  their 
caloric  from  the  combined  to  the  free  state.  It 
then  passes  off  towards  other  bodies,  and  in  its 

*  Some  chemists  consider  heat  as  the  effect  of  a  vibratory  motion  in 
the  particles  of  matter.  This  hypothesis  is  chiefly  founded  upon  the 
fact,  that  a  flame  may  be  excited  and  continued  by  friction,  greatly 
disproportioned  to  the  combustible  substances  consumed.  But  wa's 
this  experiment  ever  fairly  made  in  the  exhausted  receiver  of  the  air 
pump  ?  If  a  stick  is  put  in  the  state  of  rapid  rotary  motion  in  a  lathe, 
and  another  stick  held  against  it,  a  great  flame  will  be  produced,  by 
the  compression  of  the  air  which  is  forced  between  the  sticks  by  thi* 
rapid  motion. 


PRINCIPLE   2.       CALORIC.  29 

way  passes  into  and  expands  the  air  of  the  ther- 
mometer. 

If  the  hand  be  applied  to  the  wine  glasses  be- 
fore and  after  the  mixture  of  the  liquids,  it  will 
appear,  that  while  combined  with  the  liquids  the 
caloric  does  not  excite  the  sensation  of  heat ;  but 
that  when  pressed  out  into  a  free  state  by  the  mix- 
ture, it  does  produce  that  sensation. 

Application.  When  we  sit  by  a  fire  we  are 
warmed  by  the  caloric,  which  is  brought  out  from 
its  combined  state  with  the  oxygen  of  the  atmos- 
phere, into  a  free  state,  through  the  agency  of  the 
combustible  fuel.  Here  is  no  addition  of  caloric  ; 
for  the  air  of  the  room  held  all,  which  now  warms 
us,  in  combination,  before  we  experienced  that 
sensation. 

Prop.  4.  Caloric,  by  entering  into  combina- 
tion with  solids  in  due  proportion,  may  convert 
them  into  liquids,  and  by  encreasing  the  propor- 
tion, may  convert  the  liquids  into  vapours  or  gases. 

Illustration.  Lay  a  piece  of  ice  on  a  hot  stove 
or  fire-shovel,  it  will  soon  receive  caloric  sufficient 
to  become  water.  Let  it  remain  a  little  longer  and 
it  will  become  vapour  and  pass  off  into  the  air. 

Rationale.  The  particles  of  water  in  the  state 
of  ice  were  fixed  ;  but  caloric  being  introduced 
between  them  caused  them  to  move  freely  among 
each  other,  and  thus  become  liquid.  More  calo- 
ric being  introduced,  the  particles  were  separated 
so  widely  as  to  form  vapour  or  steam. 

Application.  When  a  kettle  of  water  is  placed 
over  the  fire,  the  particles  of  water  next  to  the  bot- 
tom first  receive  caloric  enough  to  become  vapour 
or  steam,  and  attempt  to  ascend  ;  but  the  coldev 


30  CLASS    I.      POWERS. 

water  above  robs  them  of  a  portion  of  caloric  and 
forces  them  to  remain  in  the  liquid  state.  When 
all  the  water  in  the  kettle  has  received  very  near- 
ly the  quantity  of  caloric  required  for  converting 
the  whole  into  vapour,  the  particles  next  to  the 
bottom  being  converted  into  steam  succeed  in  as- 
cending to  the  top  and  passing  off.  A  succession 
of  such  ascending  particles  of  vapour  keeps  up 
the  bubbling  called  boiling. 

Metals  are  fused  upon  the  same  principle.  The 
same  cause  also  keeps  the  atmosphere  in  the  sitate 
of  gas. 

Prop.  5.  More  caloric  is  required  for  convert- 
ing liquids  into  vapour  or  gas ,  when  the  liquids 
are  subject  to  atmospheric  pressure,  than  when 
that  pressure 9  or  any  part  of  it,  is  taken  off. 

Illustration.  Fill  a  florence  flask  one  third  full 
of  water.  Fit  a  sound  cork  to  its  mouth  perfectly 
tight.  Suspend  the  flask  with  the  mouth  open, 
over  a  candle,  lamp,  or  coals,  until  the  water 
boils.  Put  in  the  cork,  that  all  air  may  b«  ex- 
cluded which  is  driven  out  by  the  steam,  before 
the  flask  is  taken  down.  As  soon  as  the  water 
stops  boiling,  set  the  flask  on  ice,  snow,  or  in  cold 
water,  and  it  will  instantly  boil.  Hold  it  over 
the  coals  and  it  will  not  boil.  This  may  be  re- 
peated a  dozen  times  with  success.  The  flask 
may  be  passed  through  fifty  hands  after  it  is  so 
cool  as  not  to  be  painful  to  the  hand,  and  then  be 
returned,  and  still  boil  when  set  on  ice,  snow,  or 
in  very  cold  water. 

Rationale.  Water  does  not  require  212  de- 
grees of  heat  for  converting  it  into  vapour.  It  has 
been  made  to  boil  at  67  degrees  \  that  is  31  de^ 


PRINCIPLE    2.      CALORIC.  31 

grees  below  blood  heat.  Therefore  it  requires 
145  degrees  of  heat  to  resist  the  pressure  of  the 
atmosphere.  In  this  experiment  the  atmospheric 
pressure  is  taken  off,  or  most  of  it,  and  the  water 
is  left  to  boil  with  the  degree  of  heat  which  it  re- 
quires when  not  restrained  by  atmospheric  pres- 
sure. 

Application.  A  boiling  pot  which  boils  over 
with  the  lid  on,  will  often  cease  to  boil  over  when 
the  lid  is  removed.  In  this  case  there  is  not  a  va- 
cuum between  the  lid  and  the  water ;  but  the  air 
beneath  the  lid  being  driven  out  by  steam,  leaves 
room,  without  the  usual  pressure,  for  the  steam 
continually  to  follow  it  to  the  top  of  the  pot,  so  as 
to  pass  out  under  the  edges  of  the  lid.  When  the 
lid  is  taken  off,  the  pressure  of  the  atmosphere 
keeps  down  the  water  until  an  additional  degree 
of  caloric  forces  it  up  again.  It  cannot  be  said 
that  the  cold  air  which  is  let  in,  by  cooling  the 
water,  produces  this  effect ;  for  it  will  not,  if  the 
heat  is  but  about  212^  boil  over  again  with  the 
same  fire.  A  stronger  heat  is  now  required. 

Prop.  6.  Caloric  enlarges  the  volume,  and 
thereby  diminishes  the  specific  gravity  of  a  gas,  ly 
entering  into  and  combining  with  it. 

Illustration.  Bring  a  burning  coal  near  an  air 
thermometer,  and  it  will  force  the  liquid  down 
the  tube. 

Rationale.  Caloric  being  accumulated  in  one 
body  in  excess,  compared  with  the  quantity  of  it 
in  another  hody,  in  seeking  its  equilibrium  passes 
into  the  body  containing  the  less  quantity.  Thus 
\t  passes  from  the  burning  coal  into  the  atmos- 
phere about  it,  including  the  atmospheric  air  in 


32  CLASS   I.      POWERS. 

the  bulb  of  the  air  thermometer.  This  enlarges 
the  volume  and  forces  the  liquid  down,  and  out  at 
the  mouth  of  the  beak  of  the  thermometer. 

Application.  A  heated  chimney  or  stove  pipe, 
by  thus  expanding  the  air  in  it,  renders  it  of  less 
specific  gravity  than  the  surrounding  air.  The 
heavier  air  presses  into  it  of  course  ;  and  thus  a 
current,  carrying  with  it  smoke,  &c.  is  continued 
in  "that  direction.  The  same  application  of  calor- 
icj  on  a  vast  scale,  causes  winds. 

Prop.  7.  Caloric  passes  from  its  combination 
with  one  body  into  another,  which  contains  less  in 
proportion  to  its  capacity  for  caloric,  until  the  two 
bodies  are  in  equilibrio. 

Illustration.  Put  the  warm  hand  upon  the  bulb 
of  the  air  thermometer,  and  the  liquid  will  sink  at 
first  and  at  length  become  stationary.  Dip  the 
hand  in  cold  water  and  it  will  rise. 

Rationale.  The  hand  containing  more  caloric, 
in  proportion  to  its  capacity  for  caloric,  than  the 
air  in  the  thermometer,  caloric  passes  out  of  it  and 
enlarges  the- volume.  When  the  hand  is  cooled; 
the  order  is  inverted. 

Application.  Frozen  eggs  or  apples  are  thus 
gradually  thawed  in  cold  water.  Water,  not  be- 
ing frozen,  though  very  cold,  contains  more  calor- 
ic than  they  ;  consequently  caloric  passes  gradu- 
ally into  them  from  the  water  until  their  tempera- 
ture is  raised  above  freezing.  When  the  hands 
or  feet  are  frozen,  they  should  be  gradually  thaw- 
ed in  cold  water  in  the  same  way. 

Prop.  8.  Caloric  expands  jTtymds,  as  well  as 
gases,  by  entering  into  and  combining  with  them. 

Illustration.     Take  the  measure  of  the  length 


PRINCIPLE  2.       CALORIC.  S3 

of  a  cold  rod  of  iron,  which  is  about  a  foot  long 
and  cut  off  square  at  both  ends.  Heat  it  red  hot 
and  apply  it  again  to  the  same  measure  ;  and  it 
will  be  found  to  be  considerably  longer.  Cool  it 
and  apply  it  again,  and  it  will  be  found  to  fit  the 
measure  as  at  first. 

Rationale.  Caloric,  being  introduced  between 
the  particles  of  iron,  separates  them  a  little  dis- 
tance ;  though  not  so  far  as  to  bring  the  iron  to  a 
fluid  state.  - 

Application.  This  principle  causes  the  pendu- 
lums of  clocks  and  balance  wheels  of  watches,  to 
vary  in  length  according  to  the  varying  tempera- 
ture of  the  weather  ;  and  consequently  to  run  fast- 
er in  cold  and  slower  in  hot  weather. 

Prop.  9.  Caloric  expands  liquids,  as  well  as 
solids  and  gases,  by  entering  in  and  combining 
with  them. 

Illustration.  Fill  the  bulb  of  a  bolthead  with 
cold  alcohol  ;  and  on  holding  it  over  coals  or  a 
candle,  the  alcohol  will  expand,  and  consequent- 
ly ascend  into  the  neck  of  the  bolthead.  A  glass 
tube,  luted  into  the  neck  of  a  florence  flask,  filled 
with  alcohol,  will  be  quite  as  good. 

Rationale.  Caloric,  being  introduced  between 
the  particles  of  alcohol,  separates  them  a  little 
distance  from  each  other,  though  not  far  enough 
to  bring  the  alcohol  to  the  state  of  vapour. 

Application.  Thermometers  are  constructed 
by  confining  a  liquid  (quicksilver  or  alcohol  is 
generally  employed)  in  a  tube  with  a  bulb  at  the 
base,  containing  no  air.  Degrees  are  marked 
against  the  side  of  the  tube,  by  which  the  temper 
ature  is  indicated  as  the  liquid  ascends  and  de- 
scends in  the  tube.  That  all  thermometers  may 


34  CLASS    I.      POWERS. 

be  made  to  accord  with  each  other,  the  boiling 
and  freezing  of  pure  water,  are  assumed  as  start- 
ing points.  Then  the  space  of  the  tube  between 
these  points  is  cut  into  a  number  of  equal  divis- 
ions, each  of  which  is  the  measure  on  every  de- 
gree above  and  below,  as  well  as  between,  those 
points.  Fahrenheit  divides  this  space  into  180 
parts,  Reaumur  into  80,  De  Lisle  into  150,  the 
Centigrade  into  100.  We  use  Fahrenheit,  who 
begins  to  count  at  32  degrees  below  freezing,  mak- 
ing the  boiling  point  at  "2 12. 

Prop.  10,  Caloric  is  transferred  through  bod- 
ies called  conductors  ;  and  substances  differ  great- 
ly in  their  conducting  powers. 

Illustration.  Procure  a  pipe  stem  and  an  iron 
rod  of  the  same  size  and  length.  Make  a  white 
wax  or  bees  wax  head  on  one  end  of  each  about 
the  size  of  a  musket  ball.  Put  the  other  end  of 
each  close  together  on  burning  coals,  passing  them 
between  two  bricks,  in  order  to  defend  the  wax 
from  the  direct  heat  of  the  coals.  Then  raise  the 
heat  of  the  coals  with  a  hand  bellows,  and  the  head 
of  wax  on  the  iron  rod  will  melt  soon  ;  whereas 
the  wax  on  the  pipe  stem  can  scarcely  be  made  to 
melt.  Charcoal  is  a  slow  conductor  of  caloric  : 
which  will  be  well  illustrated  by  burning  one  side 
of  a  small  piece  of  charcoal,  while  it  may  be  held 
in  the  hand  by  the  other  side. 

Rationale.  Caloric  is  received  from  the  burn- 
ing coals  by  both  rods.  It  is  then  transferred  from 
particle  to  particle  along  their  whole  extent ;  hut 
it  passes  with  much  greater  velocity  from  one  par- 
ticle of  iron  to  the  next,  than  from  one  particle  of 
the  baked  clay  of  the  pipe-stem  to  the  next, 


PRINCIPLE    2.       CALORIC.  35 

Application.  An  iron  stove  soon  gives  off  ca- 
loric into  a  room  and  soon  cools  ;  whereas  a  brick 
Russian  stove  must  be  heated  a  long  time  before 
it  begins  to  give  off  caloric  into  the  room,  and  will 
not  cool  in  a  very  long  time.  Clothes  made  of 
wool  and  silk  are  slow  conductors  of  caloric  : 
those  made  of  flax  conduct  caloric  rapidly.  As 
stone  is  a  better  conductor  of  caloric  than  brick, 
a  stone  house  has  its  rooms  sooner  heated  in  sum- 
mer and  cooled  in  winter,  than  a  brick  house. 

Prop.  11.  The  same  substance  is  a  better  con- 
ductor of  caloric  if  dark  coloured  or  rough,  than  if 
bright,  polished  or  light  coloured. 

Illustration.  Scratch  and  blacken  with  lamp 
smoke  one  side  of  a  small  tin  canister.  Fit  it  to 
a  stand,  so  that  the  blackened  and  polished  sides 
may  be  readily  set  at  the  distance  of  half  an  inch 
from  the  same  side  of  the  bulb  of  an  air  thermom- 
eter. Now  fill  the  canister  with  hot  water,  and 
present  the  polished  and  blackened  sides  of  it  al- 
ternately to  the  thermometer  several  times.  The 
liquid  will  always  sink  lowest  when  the  blacken- 
ed side  is  presented. 

Rationale.  As  the  caloric  is  transmitted  through 
the  rough  blackened  side  with  the  greatest  facil- 
ity, or  rather  meets  with  less  obstruction  than  in 
passing  through  the  polished  side,  the  air  in  the 
bulb  of  the  thermometer  receives  more  caloric 
from  the  water  in  a  given  time,  and  is  consequent- 
ly more  expanded. 

Application.  A  white  earthen  teapot  will  keep 
the  tea  hot  longer  than  a  black  one.  A  bright  tin 
coffee  pot  will  keep  the  coffee  hot  longer  than  a 
japanned  one.  Light  coloured  clothes  will  keep 


36  CLASS    I.      POWERS. 

us  cooler  ill  hot  weather  and  warmer  in  cold 
weather  than  dark  coloured.  For  our  bodies  be- 
ing warmer  than  the  air  in  cold  weather,  caloric 
passes  out  through  our  clothes  ;  but  the  hot  rays 
of  the  sun  in  summer  pass  through  our  clothes  in- 
wardly. 

Prop.  12.  When  solids  are  converted  into  li- 
quids caloric  is  absorbed  from  the  adjoining  bodies. 

Illustration.  Put  a  table  spoon  of  Epsom  salts 
into  a  tumbler.  Pour  twice  as  much  cold  water, 
by  measure,  upon  it.  The  water  and  tumbler 
will  become  intolerably  cold.  If  ice  be  dissolved 
in  nitric  acid  in  the  same  manner,  it  will  give  the 
same  result.  A  freezing  mixture  may  be  made  as 
follows  :  pulverize  separately  and  very  finely, 
one  part  by  weight  of  sal  amoniac  and  one  part  of 
saltpetre.  Put  these  into  a  tumbler  and  pour  on 
them  three  parts  by  weight  of  very  cold  water. 
Now  stir  this  mixture  with  a  test  glass,  or  a  very 
thin  small  vial,  containing  half  a  teaspoon  of  cold 
water.  The  water  in  the  test  glass  will  soon  be 
frozen. 

Rationale.  The  salts  in  this  mixture,  by  their 
action  upon  each  other,  and  by  the  aid  of  the  wa- 
ter, are  brought  to  the  liquid  state.  More  caloric 
being  required  by  these  substances  for  their  liquid 
than  for  their  solid  state,  they  absorb  it  from  the 
nearest  substances.  Consequently  the  water  in 
the  test  glass  is  deprived  of  so  much  of  its  caloric^ 
as  to  be  reduced  to  the  state  of  ice. 

Application.  When  snow  has  commenced 
thawing  by  the  heat  of  the  sun  through  the  day, 
it  will  continue  to  melt  in  the  evening.  During 
the  time  it  melts  in  the  evening  it  takes  so  much 


PRINCIPLE   2.      CALORIC.  37 

caloric  from  the  atmosphere,  as  often  to  render  it 
colder  than  on  a  preceding  evening  while  water 
was  freezing  into  ice. 

Prop.  13.     While  liquids  are  converted  into  va 
your  or  gas,  caloric  is  absorbed  from  the  adjoining 
bodies. 

Illustration.     Wet  a  piece  of  thin  cotton  cloth 
in  ether  and  lay  it  on  the  bulb  of  the  air  thermom 
eter,  and  apply  a  few  drops  of  ether  to  the  cloth 
frequently,   and  the  air  in  the  bulb  will  be  con 
densed.     The  ether  should  be  quite  as  warm  as 
the  thermometer  when  applied,  to  make  the  ex- 
periment a  fair  one. 

Rationale*  More  caloric  being  required  to  con- 
vert the  ether  into  vapour,  and  the  thermometer 
being  .nearest,  it  is  robbed  of  part  of  its  caloric. 

Application.  Inflamed  tumors  are  cooled  on 
this  principle  by  frequently  wetting  with  ether- 
Rooms  are  cooled  in  hot  summer  days  by  sprink- 
ling with  water  ;  because  the  water  soon  passes 
into  vapour  and  absorbs  some  of  the  caloric  from 
the  air  of  the  room. 

Prop.  14.  When  liquids  become  solids,  com- 
bined caloric  is  evolved  or  pressed  out  and.  becomes 
free. 

Illustration.  Prepare  liquid  muriate  of  lime  as 
directed  under  lime.  Pour  half  a«poonfull  into  a 
wine  glass.  Pour  in  strong  sulphuric  acid,  until 
a  solid  is  forme'd.  On  taking  the  wine  glass  be- 
tween the  thumb  and  finger,  the  student  will  find 
it  considerably  heated. 

Rationale.  The  sulphuric  acid  having  a  supe- 
rior affinity  for  the  lime,  the  muriatic  acid  is  forced 

4 


38  CLASS   I.      POWERS. 

. 

put  in  the  state  of  gas,  leaving  solid  gypsuin  in 
the  wine  glass.  The  caloric  of  fluidity  being 
pressed  out  warms  the  glass. 

Application.  When  the  freezing  process  com- 
mences, and  water  begins  to  be  converted  into  ice, 
or  vapour  into  snow,  so  much  caloric  is  frequently 
evolved  as  very  sensibly  to  diminish  the  severity 
of  the  cold.  The  heat  produced  in  slaking  lime 
is  caused  by  solidifying  water. 

Prop.  15.  When  vapour  or  gases  become  liquidsy 
solids,  or  more  dense  vapours  or  gases,  combined 
caloric  of  the  vapour  or  gas  is  evolved  or  pressed 
out  and  becomes  free. 

Illustration.  Let  the  flame  of  burning  hydro- 
gen pass  into  a  large  dry  vial  of  atmospheric  air, 
and  water  will  be  formed  which  will  line  the  vial 
with  vapour,  and  great  heat  will  be  produced. 

Rationale.  The  burning  of  the  hydrogen  is 
carried  on  by  the  union  of  the  oxygen  of  the  atmos- 
phere with  the  hydrogen ;  which  will  be  demon- 
strated under  the  article  hydrogen.  When  the 
flame  is  confined  in  the  vial,  water,  the  product  of 
this  combustion,  is  made  manifest.  As  all  the 
heat,  or  free  caloric,  is  caused  by  this  process,  it 
follows  that  the  caloric  is  evolved  by  the  reduc- 
tion of  the  gases  to  the  liquid  state. 

Application.  All  combustion  is  explained  upon 
the  same  principle.  For  example,  successive  por- 
tions of  oxygen  coming  in  contact  with  heated 
portions  of  oil  in  a  lamp  or  melted  tallow  of  a  can- 
dle, which  are  carried  up  the  wick  by  capillary 
attraction  ;  the  oxygen  and  oil  uniting  and  form- 
ing a  more  dense  gas,  a  quantity  of  caloric  is  press- 
ed out  of  the  oxygen.  A  continued  succession 


PRINCIPLE  2.      CALORIC.  39 

of  such  combinations  pressing  out  a  continued  suc- 
cession of  portions  of  caloric,  from  the  combined 
to  the  free  state,  produces  a  continued  blaze.  All 
combustibles  have  an  affinity  for  oxygen,  and  af- 
ter combustion  are  found  to  be  combined  with 
oxygen. 

Rooms  may  be  warmed  by  steam  upon  this  prin- 
ciple. Steam  holds  a  great  quantity  of  caloric  in 
combination,  and  it  is  readily  condensed  by  a  very 
little  cold  water,  or  by  the  lower  temperature  of 
the  metallic  tubes  in  which  it  is  confined.  On  be- 
ing condensed,  as  it  passes  from  the  state  of  vapour 
to  the  liquid  state,  caloric  is  pressed  out  from  its 
combined  state  to  a  free  state,  and  thus  warms  the 
rooms. 

Prop.  1 6.  Free  caloric  is  radiated  in  all  direc- 
tions from  the  body  from  which  it  is  disengaged* 

Illustration.  Suspend  a  heated  iron  ball  by  a 
wire,  and  hold  an  air  thermometer  on  all  sides  of 
it  in  succession.  It  will  be  found  to  be  equally 
affected  at  equal  distances. 

Rationale.  As  the  thermometer  is  equally  af- 
fected on  all  sides  at  equal  distances,  it  follows, 
that  its  radiation  is  equal  in  all  directions. 

Application.  A  stove  set  in  or  near  the  centre 
of  a  room  will  afford  as  much  warmth  on  each  of 
all  its  sides,  as  it  would  on  the  one  exposed  side, 
if  set  in  a  side  fire-place. 

Prop.  17.  Caloric  is  reflected  by  hard  polished 
surfaces  like  light. 

Illustration.  Set  a  bright  tin  plate  on  one  edge. 
Set  up  a  board  on  one  edge  perpendicular  to  the 
middle  of  the  tin  plate,  so  that  its  nearest  edge 
shall  be  about  two  inches  from  the  plate.  Sus 


10  CLASS    I.       POWERS, 

pend  a  heated  ball  on  one  side  of  the  board  and 
set  an  air  thermometer  on  the  other  side,  so  that 
they  may  be  at  equal  distances  from  the  board  and 
from  the  plate.  The  thermometer  will  be  imme- 
diately affected. 

Rationale.  As  the  board  was  interposed  be- 
tween the  heated  ball  and  the  thermometer,  the 
latter  could  not  be  affected  directly.  Of  course 
the  caloric  must  have  been  conveyed  to  the  ther- 
mometer by  reflection  upon  the  tin. 

Application.  Polished  walls  of  a  room,  called 
hard  finish,  will  reflect  the  caloric  radiated  from  a 
stove,  and  thereby  cause  the  air  of  a  room,  to  be 
warmed  much  more  than  papered  walls.  A  room 
lined  with  sheet  tin  might  be  kept  warm  with  very 
little  fire,  on  this  principle. 

PRINCIPLE  3.     ELECTRICITY.* 
Natural  History  and  general  Remarks. 

The  electic  fluid  is  universally  diffused.  It 
presents  no  phenomena  which  indicate  its  pres- 
ence when  in  equilibrio.  When  its  equilibrium  is 
disturbed  and  it  is  seeking  its  restoration,  it  ex- 
hibits several  interesting  properties.  Nature  thus 
presents  it  on  a  large  scale  in  the  terrific  form  of 
lightning. 

Prop.  i.  The  electric  fluid  is  accumulated  lij 
friction,  and  manifests  itself  by  attraction  and  re- 


*  Electricity,  was  not  considered  as  belonging  to  the  department  of 
Chemistry  by  Lavoisier,  Henry,  Accura  and  others,  who  wrote  their 
systems  as  early  as  the  year  1810,  and  previous.  As  some  important 
decompositions  are  now  effected  by  the  power  of  electricity,  a  fevv 
of  its  principles  oughtto.be  illustrated ;  though  its  most  important 
phenomena  are  referrible  to  natural  philosophy. 


PRINCIPLE   3.      ELECTRICITY,  41 

Illustration.  Lay  a  half  sheet  of  paper  upon  a 
warm  smooth  board  or  table.  Rub  the  paper  smaii- 
ly  with  a  large  thick  piece  of  India  rubber,  as  if 
rubbing  out  pencil  marks,  about  a  dozen  strokes. 
Now  lift  up  one  end  of  the  paper  and  let  it  fall  back 
on  the  board,  and  it  will  go  down  with  force, 
being  moved  by  electrical  attraction.  It  will 
also  adhere  to  the  side  of  a  ceiling.  Hold  light 
down  suspended  by  fine  threads  near  the  paper, 
and  it  will  be  attracted  and  repelled  alternately. 
Hub  a  glass  cylinder,  a  stick  of  sealing  vvax,*  a 
piece  of  rosin,  amber,  or  gum-copal,  with  a  dry  silk 
handkerchief,  and  it  will  attract  and  repel  alter- 
nately, suspended  pieces  of  cork,  feathers,  tow, 
thread,  &c.  The  substance  should  be  warmed, 
and  the  experiment  should  be  made  when  the  at- 
mosphere is  dry  and  the  wind  northerly. 

Rationale.  The  electric  fluid  being  accumu- 
lated by  friction,  it  makes  an  effort  to  pass  off  to 
restore  its  equilibrium  ;  in  doing  which  it  attracts 
those  bodies.  Afterb?»inga  short  time  in  contact, 
electrified  bodies  repel  each  other,  See  Webster's 
Philosophy,  head  Electricity. 

Application.  In  cold  dry  weather,  when  the  at- 
mosphere is  always  highly  charged  with  the  elec- 
tric fluid,  our  clothes  often  exhibit  analogous  ap- 
pearances when  we  put  them  off  or  on  in  a  cold, 
room  ;  which  are  to  be  explained  on  the  same  prin- 
ciple. 

Remark.  The  electric  fluid  is  accumulated 
more  expeditiously  by  the  aid  of  an  amalgam,  as 
follows  :  Melt  one  part  of  tin  and  two  parts  of 
zinc,  and  stir  them  well  together  in  the  ladle. 
Heat  six  parts  of  mercury  so  that  water  will  hiss 
when  poured  upon -it.  Put  the  three  metals  into 

4* 


42  CLASS    I.       POWERS. 

a  warm  iron  mortar,  and  rub  them  to  a  powder 
with  a  pestle.  The  amalgam  will  now  be  prepar- 
ed for  use.  The  best  way  of  using  it  is,  to  rub 
cold  tallow  upon  a  piece  of  soft  leather,  and  then 
spread  the  amalgam  upon  tlje  tallow,  pressing  it 
on  hard  with  a  wide  knife-blade. 

Prop.  2.  The  electric  fluid  is  accumulated  by 
the  action  of  diluted  acids  upon  pairs  of  metallic 
plates,  and  tends  to  restore  its  equilibrium  in  the 
direction  of  the  metal  which  has  the  strongest  at- 
traction for  oxygen. 

Illustration.  Make  a  trough  of  baked  mahog- 
any, and  divide  it  into  half  inch  portions  by  me- 
tallic partitions.  Each  of  these  partitions  to  be 
made  of  a  plate  of  zinc  and  copper  soldered  togeth- 
er at  the  edges,  and  set  in  with  the  same  metals  the 
same  way.  Fill  these  portions  or  divisions  with  a 
liquid  consisting  of  one  part  of  sulphuric  acid,  one 
part  of  nitric  acid,  and  sixty  parts  of  water.  Now 
fit  in  a  wire  at  each  end  of  the  trough,  by  coiling 
one  end  spirally  so  that  it  will  spring  strongly 
against  the  two  extreme  metallic  plates,  when  in- 
eerted  into  the  end  cells  or  divisions.  Bring  the 
other  ends  of  the  wires^ almost  together,  and  sparks 
will  piss  from  one  to  the  other. 

Rationale.  All  the  zinc  plates  being  in  one  di- 
rection and  the  copper  plates  in  the  other,  and 
•zinc  having  a  stronger  attraction  for  oxygen  than 
copper,  the  electric  fluid  tends  to  restore  its  equi- 
librium in  the  direction  of  the  zinc  side  of  the 
•plates.  When  the  conducting  wires  are  brought 
iogether,  the  electric  fluid  passes  from  the  zinc 
(or  positive)  side  over  to  the  copper  (or  negative) 
Side. 


PRINCIPLE  4.       LIGHT.  43 

Application.  *If  an  animal,  but  recently  dead, 
be  placed  in  the  circle  with  a  proper  application 
of  the  wires  to  a  nerve  and  a  muscle,  the  animal 
"will  exibit  signs  of  life.  Airy  metal,  even  plati- 
na,  if  placed  in  the  circle  will  burn  like  tinder. 
This  application  of  electricity  is  called  GALVAN- 
ISM. 

Prop.  3.  Compounds,  of  which  one  of  the  con? 
stituents  is  oxygen,  may  be  decomposed  if  placed 
in  the  galvanic  circle — the  oxygen  always  going 
to  the  positive  side  or  pole. 

Illustration.  Place  the  two  ends  of  the  wire 
conductors  in  the  opposite  sides  of  a  wine  glass  of 
water,  and  the  oxygen  will  go  to  the  positive  pole, 
and  if  iron,  will  unite  with  it,  while  the  hydrogen 
will  rise  up  in  bubbles  from  the  negative  pole. 
Solutions  of  salts  are  decomposed  ;  the  acids  going 
to  the  positive,  and  the  bases  to  the  negative  poles. 
Acids  are  decomposed  ;  the  oxygen  going  to  the 
positive  pole  and  the  acidifiable  bases  to  the  ne- 
gative. 

Rationale.  The  same  as  in  the  last  proposition. 

Application.  By  this  mode  of  applying  elec- 
tricity, potash,  soda,  lime,  and  many  other  bodies 
may  be  decomposed,  which  resist  the  most  pow- 
erful chemical  agents. 

a 

PRINCIPLED.     LIGHT. 

Natural  History  and  general  Remarks. 

Light  is  chiefly  derived  from  the  sun,  in  the  so- 
lar system.  This  is  called  solar  light  or  celestial 
light.  It  is  also  derived  from  terrestrial  objects  ; 
as  from  combustion,  friction,  chemical  attraction; 


44  CLASS    I.      POWERS. 

&c.     This  is  called  terrestrial  light.     It  is  gener- 
ally accompanied  by  caloric. 

Every  ray  of  common  light  contains  in  itself 
seven  different  knids.  These  may  be  best  sepa- 
rated by  a  triangular  glass  prism;  but  the  same 
operation  may  b<*  performed  with  a  tumbler  of 
water.  Such  experiments,  however,  belong  to 
the  department  of  natural  philosophy.  The  seven 
kinds  of  light  differ  in  two  remarkable  charac- 
teristics 'They  are  of  different  colours  and  of  dif- 
ferent degrees  of  refrangibility.  They  are  red. 
orange,  yellow,  green,  blue,  indigo,  and  violet. 
The  red  is  least  refrangible,  the  violet  most ; 
and  the  intermediates  vary  in  their  degrees  of  re- 
frangibility according  to  this  order  of  succession. 
The  different  colouring  of  bodies  depends  on  the 
different  kinds  of  light  which  they  reflect  to  the 
eye.  White  bodies  reflect  all  kinds  of  light — 
black  reflect  none. 

Prop.  i.  The  different  kinds  of  light  are  reflect- 
ed, according  to  the  arrangement  of  the  constituent 
atoms  of  bodies  reflecting  them;  not  according  to 
the  nature  of  those  atoms.- 

Illustration.  Prepare  the  following  solutions  as 
here  directed  :  1.  Sugar  of  lead  dissolved,  1  to 
50  of  water  by  weight — 2.  Pearlash,  1  to  4  of  wa- 
ter— 3.  Corrosive  sublimate,  1  to  30  of  water — 4. 
Copperas,  1  to  6  of  water — 5.  Sulphuric  acid,  1  to 
12  of  water— 6.  Verdigris,  1  to  100  of  water— -7. 
Strong  liquid  ammonia — 8.  Tincture  of  red  cab- 
bage— 9.  Tincture  of  galls — 10.  Prussiate  of  pot- 
ash— 11.  Nitrate  of  mercury,  made  of  1  of  mercury 
to  4  of  nitric  acid,  to  which  is  added  twice  as  much 
water. 

By  mixing  these  liquids  we  make, 
Red — One  of  5  with  one  of  8. 


PRINCIPLE  4.       LIGHT,  45 

Orange — Four  of  3  with  one  of  2. 

Limpid  with  one  of  5. 
Yellow — Four  of  11  with  one  of  2. 
Green — Three  of  8  with  one  of  2. 

Ruby  red  with  one  of  5. 
Blue — Three  of  6  with  one  of  7. 

Limpid  with  one  of  5. 
Indigo — One  of  4  with  one  of  10. 
Violet — Add  the  red  to  the  indigo.  . 
White — Mix  three  of  1  with  one  of  2. 
Black — Three  of  9  with  one  of  4. 

Limpid  with  one  of  5. 

Rationale.  These  liquids  either  reflect  differ- 
ent colours  before  they  are  mixed,  from  those 
which  they  reflect  afterwards,  or  reflect  no  colours 
as  some  of  them  are  limpid.  It  follows  as  a  ne- 
cessary conclusion,  that  colouring  is  not  inherent 
in  matter,  but  depends  on  the  peculiar  arrange- 
ment of  the  constituent  atoms.  For  if  inherent  in 
matter  the  same  matter  would  always  present  the 
same  colours. 

Application.  As  colours  are  changed  by  the 
various  applications  of  the  laws  of  chemical  affin- 
ity, dyers,  limners,  &c.  ought  to  be  well  acquaint- 
ed  with  these  laws.  Mordants  sometimes  only 
fix  a  colour  b^  their  affinity  for  the  stuff  and  for 
the  colouring  matter.  In  other  cases  they  effect 
a  total  decomposition  of  the  colouring  matter,  and 
thereby  produce  new  colours. 

Prop.  2.  Light  decomposes  many  substances 
by  its  direct  action  upon  their  elementary  consti- 
tuents. 

Illustration.     Put  oxymuriatic  acid  gas  (chlo 
rine  gas)  into  a  vial,  cork  it  tight  and  set  it  in  a 
window  exposed  to  the  rays  of  the  sun.     In  a  few 


46  CLASS    I.    "POWERS. 

days  examine  it,  and  it  will  be  found  to  consist  of 
muriatic  acid  and  oxygen. 

Fill  a  bell-glass  or  large  tumbler  loosely  with 
mint,  hyssop,  savory,  or  some  other  leaves  and 
herbage,  collected  in  the  morning  before  sun-rise. 
Fill  the  same  up  with  water,  and  invert  it  in  a 
plate  filled  with  water.  This  operation  is  best 
performed  in  a  cistern  or  tub  of  water.  Set  it  in 
a  window,  exposed  to  the  rays  of  the  sun.  Bub- 
bles will  soon  appear  on  all  parts  of  the  leaves, 
which,  on  shaking  the  whole  a  little,  will  rise  to 
the  upper  part  of  the  vessel.  Towards  evening 
immerse  it  in  a  tub  of  water  or  cistern,  and  draw 
out  the  leaves  through  water.  JS  ow  experiment 
upon  this  gas,  as  in  other  cases,  and  it  will  be 
found  to  be  pure  oxygen.  Perhaps  the  best  meth- 
od will  be  to  fill  a  small  wide  mouthed  vial  with 
it,  and  test  it  by  dipping  an  extinguished  candle 
into  it ;  which  will  be  lighted  by  the  heat  of  the 
sparks  on  the  wick. 

Rationale.  In  this  case  we  can  merely  refer  to 
facts,  without  being  able  to  assign  their  cause. 
Light  eliminates  oxygen  from  its  compounds  in 
numerous  cases.  In  the  case  of  the  chlorine  or 
oxymuriatic  acid,  the  additional  portion  of  oxy- 
gen, which  converts  muriatic  acid  into  the  oxy- 
muriatic,  is  disengaged,  leaving  the  muriatic. 

Application.  The  green  colour  of  vegetables 
is  produced  by  the  action  of  light.  For  potatoe 
vines  growing  in  a  dark  cellar,  and  other  vegeta- 
bles excluded  from  light,  are  not  green.  A  pris- 
oner long  confined  in  a  dungeon  loses  his  usual 
colour  and  becomes  of  a  peculiar  white,  unlike 
those  equally  confined  where  light  is  admitted. 


PRINCIPLE   4.       LIGHT.  4? 

Prop.  3.  Light  is  radiated  from  many  sub- 
stances which  seem  not  to  belong  to  the  class  of 
luminous  bodies  ;  which  light  is  denominated  phos- 
phorescence. 

Illustration.  Rub  two  pieces  of  white  quartz 
slightly  together  in  the  dark,  and  they  will  be- 
come luminous. 

Rationale.  Jn  this  case  nothing  like  the  scin- 
tillations of  flint  and  steel  is  the  cause  of  the  lu- 
minous appearance.  Neither  is  the're  any  phos- 
phorus in  combination  with  common  quartz. 
This  and  some  other  minerals  either  absorb  light 
and  give  it  off  when  rubbed,  or  possess  a  pecu- 
liar property,  which  cannot  be  referred  to  any 
classification  of  the  phenomena  of  light. 

Application.  Some  bodies  absorb  and  give  off 
light,  as  rotten  wood,  putrid  fish,  some  artificial 
preparations,  &c.  Snow  absorbs  light  by  day, 
which  it  gives  off  at  night ;  which  may  be  demon- 
strated by  opening  a  window  in  a  dark  night  and 
the  room  will  be  actually  illuminated  consider- 
ably, 


48 
CLASS  II.   ACIDIFYING  SUBSTANCES. 

PRINCIPLE    1.       OXYGEN. 

• 

Natural  History  and  general  Remarks. 

Oxygen  is  very  generally  diffused,  though  not 
so  universally  as  caloric,  electricity  and  light. 
It  is  one  of  the  constituents  of  thjs  atmosphere  5 
composing  about  21  per  cent  of  it.  It  is  the  only 
souring  or  acidifying  principle  used  by  nature  ; 
and  probably  so  in  all  artificial  preparations.  It 
is  found  in  nature  in  the  solid,  liquid  and  gaseous 
state  ;  but  when  pure  it  is  always  in  the  gaseous 
state.  It  is  combined  with  most  of  the  metals  in 
a  solid  state  forming  what  are  called  oxids  of  met- 
als, and  also  acids  in  a  few  cases.  As  the  ores 
called  oxid  of  iron,  oxid  of  manganese,  &c.  chro- 
mic acid  in  the  chroinate  of  iron,  &c.  It  is  com- 
bined with  hydrogen  in  the  liquid  state,  forming 
water,  and  with  carbon  in  th e  gaseous  «tatey  form- 
ing carbonic  acid  gas.  The  same  acid  is  solid  in 
a  tripple  compound,  as  in  the  common  marble, 
•which  consists  of  carbonic  acid  and  lime.  In  the 
state  of  combination,  oxygen  is  found  solid  in 
primitive,  transition  and  secondary  rocks.  There- 
fore, the  earth,  the  ocean  and  the  air  abound  in  it. 

Proposition  1.  Oxygen  is  found  in  great  abun- 
dance in  combination  with  metals9  from  which  it 
may  be  disengaged  by  caloric  in  the  state  of  gas. 

Illustration.  Pulverize  the  black  oxid  of  man- 
ganese in  an  iron  mortar.  Fill  about  ten  inches 
of  a  gun-barrel  with  it.  Put  the  end  containing 
the  manganese  into  a  fire.  A  furnace  is  best ;  but 
if  the  door  of  a  common  close  stove  be  taken  off 
and  set  bottom  up,  so  that  the  gun-barrel  may  lie 


PRINCIPLE    1.       OXYGEN.  49 

in  the  notch  or  hole  in  the  bottom  of  the  door,  with 
the  lower  end  in  the  fire,  and  the  mouth  elevated, 
it  will  heat  to  good  advantage.  A  leaden  tube 
must  be  fitted  to  the  mouth  of  the  gun -barrel, 
which  leads  to  the  cistern,  passing  the  end  under 
the  funnel  in  the  moveable  shelf.  Over  this  the 
bell-glass  or  other  receiver  must  stand,  filled  with 
water.  The  leaden  tube  must  be  fitted  to  the 
mouth  of  the  gun-barrel.  No  luting  will  be  neces- 
sary. Merely  wind  a  little  wet  flax  or  tow  around 
the  pipe  and  ring  it  in  forcibly.  Then  suck  at  the 
end  of  the  leaden  tube,  so  as  to  exhaust  consid- 
erable of  the  air,  and  placing  the  tongue  over  the 
end,  wait  a  moment  to  see  whether  the  tongue  will 
be  released.  If  not,  all  is  tight.  Be  sure  to  have 
some  part  of  the  tube  considerably  higher  thai? 
the  water  of  the  cistern,  by  bending  it  arching  up 
wards.  Otherwise  water  may  get  into  the  gun 
barrel  and  cause  an  explosion  with  steam. 

The  apparatus  being  thus  prepared,  raise  the 
heat  with  charcoal  or  good  dry  hard  wood,  and 
keep  the  gun-barrel  at  a  moderate  red  heat.  Ai 
first  collect  the  gas  that  comes  over  in  a  small 
open-mouth  vial ;  the  opodeldoc  vials  will  do- 
Frequently  try  it  by  dipping  the  hot  wick  of  an 
extinguished  candle  into  it.  When  the  candle  is 
lighted  in  it  by  the  sparks  and  heat  of  the  wick, 
begin  to  save  it  for  use.  About  one  gallon  of  the 
gas  may  be  collected  from  ten  inches  of  the  Ben 
nington  manganese.  But  there  is  great  difference 
in  manganese.  Some  contains  a  great  quantity  of 
carbonate  of  iron,  and  carbonic  acid  will  come 
over  sometime  before  the  oxygen  appears. 

Red  lead,   being  oxygen  and  lead,  is  quite  as 
good  as  the  manganese  :  but  it  is  very  difficult  to 

5 


50  CLASS    II.      ACIDIFYERS. 

clear  out  the  gun^barrel  after  the  process  is  ended. 
Whereas  manganese  is  easily  emptied  out. 

Rationale.  Oxygen  is  combined  with  manga- 
nese in  a  solid  state.  By  applying  heat,  the  ca- 
loric enters  into  combination  with  the  metal  and 
the  oxygen.  The  manganese  will  not  ever  be- 
come fused  without  more  than  ten  thousand  de- 
grees of  heat,  but  the  oxygen  will  be  disengaged 
and  converted  into  gas  at  about  one  thousand  de- 
grees. It  then  comes  over  and  assumes  the  tem- 
perature of  the  atmosphere. 

Application.  We  are  taught  by  this  experi- 
ment, that  the  pure  respirable  part  of  the  air  we 
breathe  may  be  a  solid  in  combination,  and  be 
brought  back  to  air  again  by  heat. 

Prop.  2.  Some  acids  hold  their  highest  pro- 
portions of  oxygen  by  so  feeble  a  tenure,  that 
though  combined  with  a  base  in  the  state  of  a  salty 
they  will  give  it  off  in  the  state  of  gas,  ivhen  but 
slightly  heated. 

Illustration.  If  saltpetre  is  coarsely  pulveriz- 
ed and  put  into  a  gun-barrel^  and  conducted  ac- 
cording to  the  directions  for  manganese,  except- 
ing that  the  barrel  must  hardly  be  heated  to  red- 
ness, the  saltpetre  will  melt  and  boil,  and  soon  af- 
ter oxygen  gas  will  come  over. 

Rationale.  Saltpetre  consists  of  nitric  acid 
and  potash.  The  nitric  acid  parts  with  its  high- 
est portions  of  oxygen  by  being  heated,  and  the 
salt  is  reduced  to  the  nitrite  of  potash.  This  acid 
will  be  fully  described  under  Nitrogen. 

Application.  The  facility  with  which  oxygen 
is  obtained  from  saltpetre,  is  the  property  on  which 
its  use  in  the  manufacture  of  gun-powder  depends. 


PRINCIPLE    1.  "  OXYGEN.  51 

There  is  another  substance,  called  oxy  muriate  of 
potash,  from  which  pure  oxygen  may  be  obtained 
on  the  same  principle  with  much  less  heat,  and  is 
very  explosive. 

Prop.  3.     Oxygen  is  the  only  supporter  of  com 
bustion  in  the  atmosphere. 

Illustration.  Having  obtained  some  nitrogen 
gas  (which  is  the  other  constituent  of  the  atmos- 
phere) by  the  process  hereafter  to  be  described, 
fill  a  small  glass  cylinder,  or  wide  mouth  vial 
with  it,  dip  a  burning  candle  into  it,  and  the 
candle  will  be  extinguished.  Now  fill  the  same 
vessel  about  three  fourths  full  of  nitrogen,  and  fill 
up  the  remainder  with  oxygen.  Let  the  two  gases 
stand  a  few  minutes  to  mix  according  to  those 
equilibrium  laws  which  govern  their  union.  Let 
down  into  it  a  short  piece  of  a  burning  caudle  by 
a  wire,  and  it  will  burn  as  in  common  atmospheric 
air. 

Rationale.  As  the  candle  would  not  burn  in 
nitrogen  and  noAv  does  burn  after  the  introduction 
of  oxygen,  it  is  manifest  that  it  is  the  oxygen 
which  supports  the  combustion. 

Application.  When  much  of  the  oxyaen  has 
been  consumed  by  the  breathing  of  a  crowded  as- 
sembly in  a  close  room,  candles  do  not  burn  in  the 
voom  with  the  same  brilliancy. 

Prop.  4.  Oxygen  promotes  combustion  vehe- 
mently when  pure. 

Illustration.  Fill  a  glass  cylinder  with  oxygen, 
and  let  down  a  short  piece  of  a  burning  candle  in 
to  it  by  a  wire,  and  it  will  burn  vehemently. 

Rationale.  Oxygen  being  mixed  with  nitrogen 
in  the  atmosphere^  and  nitrogen  not  being  a  sup- 


52  CLASS    II.       ACIDIFYERS. 

porter  of  combustion,  the  strong  action  of  the  oxy 
gen  as  a  supporter  of  combustion  is  restrained. 
But  when  it  is  divested  of  the  nitrogen,  it  acts 
with  all  its  force. 

Application.  The  necessity  for  having  oxygen 
diluted  with  nitrogen  is  manifest ;  for  if  the  at- 
mosphere were  pure  oxygen,  all  combustible  sub- 
stances, when  once  inflamed,  would  burn  without 
controul,  to  the  destruction  of  all  the  living  beings 
inhabiting  the  earth. 

Prop.  5.     Some  metals  will  burn  vehemently, 
after  being  inflamed,  in  pure  oxygen. 

Illustration.  Coil  up  a  piece  of  fine  iron  wire, 
sometimes  called  harpsicord  wire,  which  is  about 
the  size  of  sewing  thread.  It  will  take  the  most 
suitable  form  by  winding  it  spirally  and  closely 
around  a  pipe  stem.  Let  the  coil  be  three  or  four 
inches  long,  with  the  upper  end  fitted  into  a  cork, 
which  suits  the  mouth  of  an  8  ounce  vial.  Fill  the 
vial  nearly  with  oxygen,  leaving  only  water 
enough  in  it  to  cover  the  bottom  an  inch  thick,  to 
defend  it  from  being  broken  with  the  globules  of 
hot  oxyd  of  iron  which  will  fall  upon  it.  Set  the* 
vial  on  the  table,  stopped  with  another  cork.  Now 
tie  a  small  knot  of  silk  thread  on  the  lower  end  of 
the  coil,  hold  a  piece  of  brimstone  in  the  candle 
till  it  melts  a  small  spot,  blow  out  the  blaze  of 
brimstone  and  dip  in  the  knot  of  thread.  Be  sure 
that  the  thread  and  melted  brimstone  that  adheres 
to  it,  all  do  not  exceed  in  size  a  large  pin  head. 
All  being  ready,  pull  out  the  cork  from  the  vial, 
hold  the  thumb  over  the  mouth,  and  let  an  assist 
ant  steady  the  vial.  Now  light  the  brimstone 
match  and  put  the  coil  of  wire  quickly  into  the 
vial,  fitting  in  the  cork  to  which  it  is  attached. 


1.       OXYGEX.  58 

Lift  up  the  vial  by  the  neck,  that  all  the  class  may 
see  the  wire  burn  ;  which  will  send  off  brilliant 
sparks  and  make  a  beautiful  exhibition. 

If  a  wire,  which  is  about  twice  as  large  as  the 
coil,  be  flattened  with  si  hammer,  and  so  fitted  into 
the  cork  as  to  extend  down  through  the  centre  of 
the  coil,  and  it  be  set  on  fire  at  the  same  time,  and 
in  the  same  manner  with  the  coil,  it  will  present  a 
very  curious  appearance.  The  central  wire  will 
burn  with  a  large  globular  flame,  while  a  smaller 
globular  flame  will  perform  revolutions  around  it, 
resembling  the  motion  of  a  -planet  around  the  sun. 
If  a  still  finer  wire  is  coiled  around  the  first  coil 
and  ignited,  a  moon  will  be  seen  revolving  around 
the  planet,  while  the  planet  revolves  around  the 
sun. 

Hationale.     Same  as  in  Prop.  4. 

Application.  From  this  experiment  it  appears, 
that  if  the  oxygen  of  the  atmosphere  were  not  di- 
luted or  reduced  in  power  by  nitrogen,  even  iron 
would  not  resist  combustion.  Our  iron  stoves 
would  burn  with  the  fuel  put  into  them ;  the 
smith's  hammer  and  anvil  would  blaze  like  tin- 
der. 

Prop.  6.  Oxygen  is  the  acidifying  or  souring 
jjrinciple. 

Illustration.  Fill  an  opodeldoc  vial  with  oxy- 
gen, leaving  half  a  spoon-full  of  pure  water  in  the 
bottom.  Put  a  piece  of  phosphorus,  of  the  size  of 
a  pea,  into  a  mustard  spoon  or  a  strip  of  tin  bent 
in  the  same  form.  Suspend  it  from  the  end  of  a 
large  piece  of  wire  or  iron  rod,  forming  a  conven- 
ient handle  to  move  it  with.  All  being  ready, 
pull  the  cork  out  of  the  vial  and  liold  the  thumb 


54  CLASS    II.       ACIDIFYERS, 

upon  it;  let  an  assistant  steady  the  vial  and  hold 
a  candle  with  the  blaze  very  near  the  mouth  of  it. 
Now  take  off  the  thumb,  touch  the  phosphorus  to 
the  candle,  and  in  the  same  instant  let  it  down 
into  the  vial  of  oxygen.  It  will  burn  most  brilliant- 
ly and  probably  crack  the  vial.  A  white  floccu- 
lent  substance  will  line  the  vial.  Whether  the 
vial  breaks  or  not,  rinse  off  this  white  substance  in 
the  water  in  the  bottom  of  the  vial.  Now  pass 
this  liquid  about  in  wine  glasses,  and  the  class 
will  perceive  that  something  has  given  acidity  to 
the  phosphorus. 

Rationale.     As   nothing  but  phosphorus  and 
oxygen  were  in  the  vial,  with  the  little  water  in 
the  bottom  of  it,  the  acidity  of  the  water  must  have 
been  caused  by  the  union  of  the  oxygen  and  phos 
phorus. 

Application.  This  applies  to  all  acids,  as  will 
be  shown  under  each. 

NOMEN  CL  ATU  #E. 

Oxygen  enters  into  combination  with  acidifiable 
substances,  in  several  definite  proportions,  which 
requires  a  peculiar  nomenclature.  When  combin- 
ed in  the  lower  proportions,  they  are  called  oxids. 
or  oxides, inthv  higher  proportions  they  are  called 
acids.  The  proportions  of  oxygen  in  the  oxids 
are  expressed  by  the  Greek  numerals.  As  pro- 
toxid,  deutoxid,  tritoxid,  and  peroxid.  For  ex- 
ample, the  metal  called  manganese  is  said  to  com- 
bine with  four  definite  proportions  of  oxygen, 
forming  the  protoxid  of  manganese,  the  deutoxid 
of  manganese,  the  tritoxid  of  manganese,  and  the 
jperoxid  of  manganese*  Some  metals  do  nat 


PRINCIPLE    2.       CHLORINE.  55 

unite  with  oxygen  in  more  than  one  proportion, 
some  with  two,  some  with  three,  none  more  than 
four. 

The  proportions  of  oxygen  in  acids  is  expressed 
by  the  terminations  ous  and  ic.  As  sulphurous 
and  sulphuric  acid.  When  acids  contain  more 
than  two  proportions  of  oxygen,  the  term  hypo  is 
prefixed  to  the  name  next  below  which  it  stands. 
As  hypo-sulphuric  acid,  implies  an  acid  compos- 
ed of  sulphur  and  the  next  proportion  of  oxygen 
below  that  contained  in  sulphuric  acid.  Hypo-sul- 
phurous acid  would  express  the  acid  which  con- 
tained a  definite  proportion  of  oxygen,  next  below 
that  contained  in  sulphurous  acid.  If  the  acid 
combines  with  higher  proportions  of  oxygen  than 
that  expressed  by  the  termination  zc,  they  are  ex- 
pressed by  oxygenated  and  by  hyper.  As  muri- 
atic acid,  when  combined  with  one  higher  propor- 
tion, is  called  oxygenated  muriatic  acid — when 
two  proportions,  hyper-oxygenated  muriatic  acid. 
Oxygenated  is  usually  abbreviated,  so  as  to  form 
oxy-muriatic. 

Some  oxids,  which  are  in  the  state  of  gas,  are 
expressed  by  substituting  the  adjectives  in  ous 
and  ic  for  the  Greek  numerals.  Thus  we  say  ni- 
trous oxid  and  nitric  oxid. 

PRINCIPLE  2.     CHLORINE, 
Natural  History  and  general  Remarks. 

tjhlorine  is  an  artificial  substance.  If  simple,  it 
exists  in  nature  in  a  state  of  combination  with  hy- 
drogen, forming  muriatic  acid.  Whether  simple 
or  compound,  has  been  a  subject  of  much  discus- 
sion ;  though  the  question  is  immaterial  in  respect 


56  CLASS    II.      ACIDIPYERS. 

to  its  use  in  the  arts.  The  question  ought  to  be  de- 
cided by  bringing  chlorine  and  ammonia  together 
in  the  state  of  perfectly  dry  gases.  According  to 
Murray,  muriate  of  ammonia  and  some  water  are 
always  produced.  If  so,  chlorine  must  be  a  com- 
pound of  muriatic  acid  and  oxygen.  Its  oxygen 
goes  to  a  part  of  the  hydrogen  of  the  ammonia 
and  forms  Avater,  while  the  muriatic  acid  unites 
with  the  remainder  of  undecomposed  ammonia. 
But  Davy  says,  these  gases  may  be  so  well  dried, 
that  they  may  be  united  without  producing  any 
water.  Students  who  are  desirous  to  examine  the 
arguments  on  both  sides,  may  read  Cooper's  note 
to  Chlorine,  in  his  American  edition  of  Thomp- 
son's Chemistry. 

Muriatic  acid  is  the  substance  in  which  we  are 
to  consider  the  natural  history  of  chlorine;  for 
chlorine  is  obtained  from  it,  either  by  adding  oxy- 
gen to  it,  or  by  divesting  it  of  its  hydrogen.  Mu- 
riatic acid  being  one  of  the  constituents  of  common 
salt,  it  is  as  extensive  as  the  waters  of  the  ocean, 
the  waters  of  salt  springs,  and  the  mines  of  solid 
salt. 

It  may  be  proper  to  add,  that  some  of  the  advo- 
cates for  the  chlorid ic  theory,  consider  common 
table  salt  as  analagous  to  the  oxlds.  That  it  is 
the  chlorid  of  sodium,  arid  not  a  salt. 

Prop.  1.  Chlorine  is  obtained  in  the  state  of  gas 
from  common  table  salt  by  the  aid  of  the  oxid  of  a 
metal,  and  a  strong  acid. 

Illustration.  Put  into  a  half  pint  retort  a  pul- 
verized mixture,  well  rubbed  together,  consisting 
of  a  tea  spoon-full  of  manganese  with  twice  as 
much  table  salt.  Then  pour  into  the  retort  about 
two  tea  spoons  of  sulphuric  acid,  with  half  as 


PRINCIPLE   2.      CHLORINE.  57 

much  water.  Apply  the  heat  of  a  candle  to  the 
retort,  and  the  chlorine  gas  will  come  over.  Ifc 
ought  not  to  be  collected  in  the  cistern ;  for  the 
cistern  water  will  give  off*  a  disagreeable  odour 
for  many  days  afterwards.  Invert  the  receivers 
in  a  large  wash-bowl,  and  let  the  water  he  warm 
to  prevent  the  absorption  of  the  gas. 

As  this  gas  is  destructive  to  the  lungs,  very 
small  quantities  should  be  used  in  the  laboratory. 
Opodeldoc  vials,  (used  as  receivers)  should  be 
prepared,  filled  with  water,  and  inverted  in  the 
bowl,  before  the  process  commences.  Just  vials 
enough  should  be  filled  for  the  proposed  experi- 
ments ;  then  the  retort  should  be  instantly  carried 
out  of  the  room.  The  vials  should  be  corked 
closely,  and  the  water  immediately  thrown  out 

Rationale.  This  process  is  explained  on  two 
very  different  hypotheses.  Lavoisier,  Berzelius, 
Murray  and  others,  say  that  the  muriatic  acid,  be- 
ing disengaged  from  the  soda,  and  oxygen  from 
the  manganese,  the  muriatic  acid  unites  with  a  de 
finite  proportion  of  oxygen,  and  forms  the  oxy~ 
muriatic  acid  ;  that  is,  this  gas  consists  of  muriat- 
ic#  acid  with  an  additional  proportion  of  oxygen. 
Davy  and  others  say,  that  the  oxygen  disengaged 
from  the  manganese  unites  with  a  portion  of  hy- 
drogen, and  forms  water;  which  hydrogen,  they 
say,  combined  with  chlorine,  formes  the  muriatic 
acid.  The  chlorine  being  thus  divested  of  the  hy- 
drogen, which  held  it  in  the  state  of  muriatic  acid, 
comes  over  a  purej  simple,  yellowish  green,  suffo- 
cating £as. 

£5   S3 

Application.  On  this  principle,  and  by  a  more 
economical  use  of  the  same  substances,  the  same 
gas  is  obtained  and  combined  with  water,  to  form 


58  CLASS    II.      ACIDIFYERS. 

the  bleaching  liquor.  But  the  gas  is  ofteu  disen- 
gaged in  large  quantities  from  the  water,  when  its 
temperature  is  a  little  raised  ;  which  is  very  suf- 
focating and  injurious  to  the  health  of  workmen. 
To  remedy  this  inconvenience,  the  chlorine  is  uni- 
ted to  lime,  forming  an  oxy muriate  or  chlorid  of 
lime.  See  this  subject  again  under  lime. 

Prop.  2o  Chlorine  gas  feebly  supports  com- 
bustion, and  inflames  some  substances  spontane- 
ously. 

Illustration.  Fill  an  opodeldoc  vial  with  the 
gas.  Immerse  a  short  piece  of  a  burning  candle 
in  it,  held  upright  by  a  wire.  It  will  burn  a  short 
time  with  a  deep  coloured  flame  and  much  dense 
smoke. 

Fill  another,  and  immerse  in  it  a  small  piece  of 
phosphorus,  in  a  mustard  wpoou.  It  will  take  lire 
and  burn  spontaneously. 

Fill  another,  and  immerse  in  it  gold,  silver  and 
copper  leaf,  they  will  soon  take  fire  spontaneous- 
ly. Brass  or  copper  wire  will  burn  in  this  gas, 
if  immersed  in  a  vial  of  it  when  heated  to  redness 
in  a  candle.  For  all  these  experiments  the  gas 
must  be  just  made  and  kept  warm. 

Rationale.  Those  who  consider  chlorine  as 
muriatic  acid  with  an  additional  portion  of  oxy- 
gen, say,  the  candle  burns  with  the  additional 
portion  of  oxygen,  which  the  muriatic  acid  readi- 
ly parts  with.  And  that  the  action  of  the  acid, 
combined  with  the  excess  of  oxygen,  causes  the 
spontaneous  combustion.  Those  who  consider 
chlorine  as  a  simple  substance,  say,  these  cases  of 
combustion  are  evidence  that  it  is  entitled  to  a 
place  in  this  class  with  oxygen  ;  and  that  it  sup- 
ports combustion  of  itself  independently  of  oxy 
gen. 


PRINCIPLE  2.       CHLORINE.  59 

Application.  The  facility  with  which  chlorine 
inflames  combustible  substances,  renders  salts 
made  with  it  very  suitable  for  fire- works.  Oxy- 
muriate  of  potash  readily  inflames  many  combus- 
tible substances  by  mere  compression  in  contact 
with  them. 

Prop.  3.  Chlorine  extinguishes  vegetable  col" 
mirs,  if  the  substances  to  be  operated  upcn  are 
moistened,  or  if  the  chlorine  is  in  a  liquid  state. 

Illustration.  Obtain  chlorine  in  the  liquid  state,, 
as  follows  :  Fill  a  strong  quart  decanter  one  third 
full  of  water.  Put  into  it  a  pulverized  mixture, 
consisting  of  half  a  gill  by  measure  of  red  lead  and 
a  gill  of  common  table  salt,  well  rubbed  together. 
After  shaking  it  up,  put  into  the  decanter  two 
thirds  of  a  wine  glass  of  sulphuric  acid.  Put  in 
a  ground  glass  stopper  loosely,  and  shake  the  de- 
canter half  a  minute.  The  .atmospheric  air  and 
some  gas  will  escape.  Now  press  in  the  glass  stop- 
per perfectly  tight  and  plunge  the  decanter  into  a 
tub  or  cistern  of  cold  water,  just  keeping  the 
mouth  above  water.  Agitate  it  as  much  as  may 
be  done  under  water,  about  once  each  minute,  for 
fifteen  minutes.  Now  take  it  out  and  let  the  ex- 
cess of  red  lead  and  salt  settle.  The  sulphuric  acid 
must  never  be  in  excess.  The  liquid  will  now  be- 
come yellowish-green,  and  will  be  tolerably  pure ; 
though  it  will  contain  a  little  muriatic  acid.  Pour 
a  little  into  a  wine  glass,  and  with  it  wash  out 
writing  from  paper,  and  extinguish  the  colours 
from  calico. 

Fill  an  8  ounce  vial  with  the  chlorine  gas.  Wet 
or  dampen  one  end  of  a  piece  of  calico,  and  insert 
it  into  the  vial  by  the  side  of  the  cork,  leaving  the 
dry  end  out.  The  wet  end  in  the  vial  will  soon 
become  faded. 


60  CLASS    II.      ACIDIFYERS* 

Rationale.  The  chlorine  becomes  muriatic  acid 
by  parting  with  its  oxygen.  And  it  has  been  found, 
by  the  use  of  sulphurous  acid  and  of  some  other 
compounds,  that  oxygen  thus  imparted  will  extin 
guish  vegetable  colours. 

Application.  The  liquid  chlorine  obtained  in 
this  way  may  be  kept  in  vials  in  a  dark  cool  place, 
and  used  for  taking  spots  out  of  linen,  &c.  It  has 
been  employed  for  fraudulent  purposes,  to  oblite- 
rate written  instruments  so  as  to  write  something 
different  in  the  same  place. 

This  may  be  readily  detected  by  prussiate  of 
potash.  For  wherever  it  has  been  applied,  the 
place  will  become  green  on  the  application  of  a 
solution  of  prussiate  of  potash. 

t  Prop.  4.  Muriatic  acid,*  from  winch  chlorine 
is  made,  is  obtained  from  common  table  salt  by 
elective  ajjinitij. 

Illustration.  Fill  two  or  three  vials  or  small 
cylinders  with  mercury  and  invert  them  in  the 
trough.  Lute  very  firmly  a  pipe  bowl  to  the  mouth 
of  a  tubulated  half  pint  retort,  with  half  an  inch  of 
the  stem  remaining,  which  must  point  upwards. 
Having  previously  dried  some  fine  salt  on  an 
earthen  plate,  put  into  the  retort,  through  the  tu- 
bulature,  a  wine  glass  full  of  the  salt.  Place  the 
retort  in  a  fixed  steady  position,  with  the  beak  in 
the  trough,  so  as  to  immerse  the  pipe  bowl  and 
stem  uader  the  mercury ;  but  do  not  place  any  of 
the  receivers  in  a  situation  to  collect  the  gas  yet. 
All  being  ready,  now  pour  gradually  into  the  re- 

*  Muriatic  acid  was  supposed  to  consist  of  an  unknown  base  com- 
bincd  with  oxygen,  until  the  chloridic  theory  was  introduced.  Many 
able  chemists  still  believe  in  the  old  hypothesis;  and  consider  the  new 
one  as  an  unnecessary  anomaly. 


PRINCIPLE    2.       CHLORINE.  61 

tort,  through  the  tubulature,  as  much  strong  sul- 
phuric acid  as  will  be  sufficient  to  moisten,  or  ra- 
ther wet,  the  salt.  Considerable  gas  will  be  given 
off  immediately  and  pass  out  at  the  tubulature  ; 
but  not  more  than  is  necessary  for  driving  out  the 
air  and  vapour  which  were  in  the  retort.  Put  in 
the  stopper,  and  let  the  gas  waste  a  few  seconds 
through  the  pipe  stem.  Now  move  one  of  the  re- 
ceivers to  receive  the  gas,  setting  it  down  so  as  to 
bring  the  pipe  stem  a  little  way  into  the  mouth  of 
the  receiver,  whether  a  vial  or  glass  cylinder ;  be- 
cause the  gas  will  not  ascend  into  it  if  merely 
brought  under  it,  as  the  practice  is  when  receivers 
are  filled  with  water.  Two  or  three  small  re- 
ceivers will  now  be  soon  filled  with  pure  muriatic 
acid  gas.  But  if  a  sufficient  quantity  does  not 
come  over,  apply  a  candle  to  the  retort.  This  gas 
may  be  collected  for  ordinary  experiments,  with- 
out a  mercurial  trough.  As  it  is  heavier  than  at- 
mospheric air,  set  an  8  ounce  vial  on  the  table  in- 
clined a  little  to  one  side,  and  insert  the  neck  of 
the  retort,  extending  its  beak  to  the  bottom  of  the 
vial.  The  gas  will  soon  force  out  the  air  and  fill 
the  vial.  A  goose  quill  with  the  feathered  end  dip- 
ped in  liquid  ammonia  may  be  used  to  determine 
when  the  vial  is  full.  For  the  ammonia  will 
form  a  cloud  about  the  mouth  of  the  vial  when  it 
is  filled  and  runs  over.  Several  vials  may  be  filled 
and  corked  tight ;  each  to  be  used  for  a  separate 
experiment. 

Rationale.  Common  salt  consists  of  muriatic 
acid  and  soda.  The  soda  elects  the  sulphuric 
acid,  and  excludes  the  muriatic ;  forming  Glauber's 
salts,  which  remain  in  the  retort. 

Application.    On  this  principle  the  muriatic 
6 


62  CLASS    II.      ACIDIFYERS. 

acid,  called  spirits  of  salt,  which  is  used  by  ar- 
tists, may  be  obtained.  For  if  the  gas  be  passed 
into  a  receiver  containing  water,  the  water  will  ab- 
sorb it  and  the  common  liquid,  muriatic  acid  of  the 
shops,  will  be  formed. 

Prop.  5.  Muriatic  acid  is  strongly  absorbed  by 
water  or  ice. 

Illustration.  When  the  muriatic  acid  has  al- 
most ceased  to  come  over  by  the  last  described 
process,  take  up  the  retort,  pull  off  the  pipe  bowl 
and  set  the  mouth  in  water,  holding  the  neck  in  a 
vertical  position.  The  water  will  ascend  in  the 
neck  of  the  retort,  and  at  length  fill  it. 

Cut  a  piece  of  ice  of  a  suitable  form  for  entering 
the  mouth  of  one  of  the  vials  of  gas,  and  pass  it 
in  through  the  mercury.  It  will  become  liquid, 
and  mercury  will  ascend  and  fill  the  vial.  Invert 
one  of  the  vials  of  gas  and  place  its  mouth  in  a 
bowl  of  water.  The  water  will  ascend  and  fill  it. 

Rationale.  Water  absorbs  muriatic  acid  gas 
so  powerfully,  that  it  combines  with  it  immediate- 
ly. Its  volume  being  thus  reduced  to  almost  no- 
thing, a  vacuum  is  formed  into  which  the  water 
or  mercury  rushes  by  force  of  atmospheric  pres- 
sure. 

Application.  The  strong  attraction  existing  be- 
tween muriatic  acid  and  water,  still  exists  when 
the  acid  is  combined  with  soda  in  the  state  of  salt. 
This  accounts  for  the  salt's  forcing  ice  into  the 
liquid  state  when  they  are  used  together  for  a 
freezing  mixture — also,  when  salt  is  used  for 
thawing  out  a  pump,  &c. 

Prop.  6.  Muriatic  acid  gas  extinguishes  flame f 
first  giving  it  a  green  tinge. 


PRINCIPLE    2.       CHLORINE.  63 

Illustration.  Let  down  a  short  piece  of  candle 
slowly  into  an  opodeldoc  vial  of  the  gas.  As  the 
candle  enters  the  gas,  a  green  ring  will  encircle 
the  base  of  the  flame.  On  immersing  it  a  little 
farther,  it  will  be  extinguished. 

Rationale.  Though  muriatic  acid  gas  extin- 
guishes flame,  it  gives  a  green  tinge  to  it  after  mix- 
ing with  the  nearest  portion  of  atmospheric  air. 

Application.  This  experiment  seems  to  shew, 
that  the  muriatic  acid  possesses  some  faint  vestige 
of  that  property  of  the  chlorine  which  enables  it 
to  support  combustion. 

Prop.  7.  Muriatic  acid  may  be  arrested  in  wa- 
ter standing  over  common  salt,  at  the  moment  of  its 
escape  ;  forming  the  liquid  spirits  of  salt,  or  the 
muriatic  acid  of  the  shops 

Illustration.  Having  heated  common  table  salt 
in  a  crucible  to  a  moderate  red  heat  and  let  it  cool, 
put  an  ounce  into  a  tubulated  pint  retort.  Pour 
through  the  tubulature,  upon  the  salt,  the  same 
weight  of  diluted  sulphuric  acid,  consisting  of 
equal  measures  of  the  best  sulphuric  acid  of  the 
shops,  and  water,  after  they  had  been  mixed  and 
cooled.  Then  distil  over  the  liquid  muriatic 
acid.  This  may  be  easily  done,  by  fitting  the 
neck  of  the  retort  to  a  receiver,  immersed  in  cold 
water  or  surrounded  with  ice  or  snow,  and  apply- 
ing a  very  moderate  heat  to  the  retort.  A  sand 
bath,  or  coals  in  a  lead  pot,  will  give  a  due  degree 
of  heat. 

Rationale.  The  muriatic  acid  is  disengaged 
from  the  soda,  as  when  we  obtain  it  in  the  state  of 
gas  ;  but  it  is  arrested  in  the  water  which  is  mixed 
with  the  sulphuric  acid.  On  distillation  the  mu- 
riatic acid  and  water  come  over  in  vapour,  and  are 


64  CLASS    IIo      ACIDIFYERS. 

condensed  into  a  liquid,  leaving  the  sulphate  of 
soda  in  the  retort. 

Application.  By  this  method  a  physician  or 
an  artist  may  obtain  the  acid,  whose  purity  he  is 
acquainted  with,  by  very  little  labour  or  expense. 
And  in  the  same  experiment  we  illustrate  the  doc- 
trine of  elective  affinity,  forcible  attraction,  and  the 
motion  of  caloric  in  evaporation  and  condensa- 
tion. 

PRINCIPLE  3.     FLUORINE. 
Natural  History  and  general  Remarks. 

Fluoric  acid  is  chiefly  found  in  combination 
with  lime,  constituting  the  fluor  spar.  From  its 
analogy  to  other  acids,  it  was  supposed  to  have  an 
acidifiable  base,  which  is  combined  with  oxygen. 
This  base  was  never  discovered.  The  acid  so 
nearly  resembles  the  muriatic  acid,  that  it  seemed 
necessary  to  suppose,  that  it  consisted  of  hydro- 
gen and  a  simple  substance  analogous  to  chlorine. 
Therefore  to  accommodate  the  chloridic  theory,  a 
fluorine  is  assumed,  with  little  or  no  evidence. 

Fluoric  acid  has  been  found  in  topaz,  and  in  a 
few  other  minerals;  but  it  is  always  obtained 
from  fluor  spar  when  used  in  the  arts. 

Prop.  1.  Fluoric  acid  dissolves  flint  and  glass. 
It  is  found  constituting  an  essential  part  of  fluor 
spar,  from  which  it  may  be  obtained  in  the  state  of 
gas,  by  elective  affinity. 

Illustration.  Put  into  the  etching  box  a  tea 
spoon  full  of  coarsely  pulverized  fluor  spar,  and 
set  the  box  into  a  dripping  pan  of  coals  placed  on 
bricks  upon  the  table.  Pour  in  strong  sulphuric 
acid,  just  sufficient  to  moisten  or  moderately  wet 


PRINCIPLE    3.       FLUORINE.  65 

the  fluor  spar.  Fluoric  acid  will  immediately  rise 
up  out  of  the  cup,  which  may  he  known  hy  its  at- 
tracting so  much  vapour  from  the  air  as  to  exhibit 
the  appearance  of  common  steam.  As  soon  as  it 
begins  to  appear,  which  will  be  in  a  few  seconds, 
lay  over  the  cup  a  piece  of  common  window  glass, 
large  enough  to  cover  its  mouth,  which  had  been 
previously  waxed  and  written  upon.  Let  an  as- 
sistant instantly  apply  snow,  ice,  or  cold  water,  to 
the  upper  side  of  the  glass,  in  order  to  keep  it  so 
cool  as  to  prevent  the  wax  which  is  on  the  under 
side  from  melting.  Take  off  the  glass  in  ten 
seconds  and  apply  another,  and  so  on.  Two-  or 
three  may  be  applied  before  the  fluor  spar  and  sul- 
phuric acid  are  renewed.  The  writing  made  in 
the  wax  will  appear  beautifully  etched  upon  the 
glass  on  scraping  off  the  wax. 

The  best  method  of  preparing  the  glass,  is  to 
warm,  or  rather  heat  moderately,  the  face  of  a 
smoothing  iron  or  piece  of  polished  marble,  so 
that  white  wax  or  very  fine  beeswax  will  melt  on 
being  applied  to  it.  Lay  the  glass  flat  upon  the, 
melted  wax,  and  on  sliding  it  off,  it  will  be  very 
evenly  waxed.  A  dozen  pieces  or  more  may  be. 
prepared  in  succession.  The  writing  may  be 
made  with  the  end  of  a  hard  stick,  nail,  &c.  Care 
must  be  taken  to  lay  the  glass  perfectly  bare 
throughout  all  the  strokes,  or  there  will  be  inter- 
ruptions in  the  etching. 

Rationale.  The  lime  elects  the  sulphuric  acid, 
and  excludes  the  fluoric  in  the  state  of  gas.  This 
gas  has  a  strong  affinity  for  silex,  with  which  it 
unites  and  forms  a  fluo-silicious  gas,  leaving  the 
etched  channels. 

Application.    Any  devise,  name*  stanza^  &ca 


66  CLASS   II.      ACIDJFYERS, 

may  be  etched  in  this  way,  not  only  upon  glass, 
but  upon  any  silicious  substance.  Common  flint, 
common  chalcedony,  the  carnelion,  &c.  may  be  en- 
graved in  the  same  manner. 

PRINCIPLE  4,     IODINE. 

Natural  History  and  general  Remarks. 

'  Iodine  is  obtained  from  barilla  (the  coarse  im- 
pure soda,)  or  from  the  sea  weeds  from  which  the 
barilla  is  obtained.  Whether  it  exists  as  a  ready 
formed  simple  substance  in  the  sea  weed,  or  wheth- 
er it  is  a  compound,  produced  in  the  process  of 
obtaining  it,  is  not  known  It  possesses  several 
properties  in  common  with  chlorine.  Being  al- 
ways in  connexion  with  muriatic  acid,  it  may  be  a 
compound  of  that  substance,  somewhat  analogous 
to  the  combination  of  muriatic  acid  with  oxygen, 
in  forming  chlorine.  But  as  it  has  not  yet  been  de- 
composed, it  is  treated  as  a  simple  substance.  To 
call  a  substance  simple,  merely  because  it  has  not 
been  decomposed,  is  a  rule  adopted  when  it  will 
aid  in  the  cause  of  a  favorite  hypothesis  only. 
Muriatic  acid  and  fluoric  acid  were  always  con- 
sidered as  compound  from  mere  analogy,  when 
neither  of  them  was  supposed  to  have  been  decom- 
posed. And  it  is  not  probable  that  any  one  would 
have  even  suspected  iodine  to  be  a  simple  sub- 
stance, had  it  not  been  necessary  for  the  support 
of  the  chloridic  theory.* 

*We  have  a  remarkable  specimen  of  curious  reasoning  in  support 
of  a  favorite  hypothesis  in  some  of  the  writings  of  Sir  Humphrey  Da- 
vy. He  says,  that,  according  to  the  sound  logic  of  chemistry,  chlorine 
and  iodine  must  be  considered  as  simple  substances,  because  they  have 
faot  been  decomposed.  But  in  support  of  another  favourite  hypothesis 
•f(tnat  all  earths  have  metallic  bases,  and  must  be  classed  with  metals.) 
jhe  assumes,  from  analogy  merely,  that  alumine,  glycine,  zincoa  and 


PRINCIPLE    4.       IODINE.  67 

Iodine  at  the  common  temperature,  is  in  the 
state  of  solid  scales,  of  a  steel-grey  colour.  In 
this  it  differs  from  chlorine,  which  is  in  a  state  of 
gas  when  pure. 

Prop.  1.  Iodine  be  comes  it  purple  gas  on  rais- 
ing the  temperature  a  little. 

Illustration.  Put  a  few  scales  of  iodine  into  a 
test  glass  or  small  vial.  Cork  the  vial  quickly  to 
prevent  much  air  from  coming  in  contact  with  it. 
Warm  the  vial  over  coals,  until  the  scales  are  con- 
verted  into  a  purple  gas.  Immerse  the  vial  in  cold 
water  or  snow,  and  the  purple  gas  will  return  to 
solid  scales. 

Rationale.  At  the  common  temperature  this 
substance  is  a  solid ;  but  by  giving  it  more  caloric 
it  becomes  a  gas. 

Application.  This  experiment  shows  that  the 
same  substance  may  change  its  colour  by  merely 
receiving  an  additional  portion  of  caloric. 

Prop.  2.  Iodine  gives  different  colours  to  dif- 
ferent substances. 

Illustration.  Put  a  few  scales  of  iodine  into  a 
tea  spoon  of  alcohol  in  a  wine  glass,  it  will  give  a 
reddish  purple  colour.  Put  a  few  scales  into  a 
solution  of  starch,  and  it  will  give  a  dark  purple 
colour.  Put  a  few  scales  on  a  bright  silver  dollar, 
and  it  will  give  an  iridescent  hue.  Rub  a  few 
scales  between  the  fingers,  and  it  will  give  to  the 
skin  a  dirty  yellow  colour. 

Rationale.  We  can  only  refer  these  results  to 
the  general  proposition  under  light ;  that  different 

yttria,  are  compounds  of  different  metals  and  oxygen ;  though  they 
have  never  been  decomposed,  nor  a  shadow  of  evidence  of  their  com- 
pound nature  has  hitherto  been  deduced  from  experiment, 


68  CLASS    II.       AC1DIFYERS, 

colours  depend  on  the  different  arrangement  of 
constituent  atoms. 

Application.  The  above  solution  in  alcohol 
is  used  by  physicians  in  the  scrofula.  The  other 
combinations  are  subjects  of  curiosity  only.  See 
New-York  Medical  and  Physicial  Journal,  p. 
263;  519. 

NOMENCLATURE, 

A  peculiar  nomenclature  has  been  introduced 
for  chlorine  and  iodine,  when  in  combination  with 
other  substances.  Considering  them  as  analogous 
io  oxygen,  their  nomenclature  is  also  analogous. 
If  uncompounded  chlorine  or  iodine  is  united  with 
a  metallic  base,  the  compound  is  called  a  chlorid 
or  iodid  of  that  metal.  When  they  arc  supposed 
to  be  united  with  oxygen,  the  termination  is  in  ic. 
as  in  other  compounds  of  oxygen  where  an  acid  is 
formed,  &c.  A  comparative  view  of  the  nomen- 
clature of  those  who  do,  and  of  those  who  do  not. 
believe  these  to  be  simple  substances,  will  suffi- 
ciently illustrate  this  nomenclature.  Chlorine  and 
iodine  are  oxymuriatic  acid  and  oxiodiatic  acid. 
Hydrochloric  acid  and  bydriodic  acid  are  muriatic 
acid  and  iodiatic  acid.  Chloric  acid  and  iodic 
acid  are  hyperoxymuriatic  acid,  and  hyperoxiodi- 
atic  acid.  Their  salts  are  expressed  by  termina- 
ting the  names  of  their  acids  in  ate  and  ite,  as  will 
be  explained  hereafter,  in  regard  to  sajts  in  gener- 
al. 


69 


CLASS  HI.    OX1DABLE  SUBSTANCES, 
NOT  METALLIC. 

PRINCIPLE    1.       HYDROGEN. 

Natural  History  and  general  Remarks. 

As  water  is  a  compound  of  hydrogen  and  oxy- 
gen, it  is  as  extensively  diffused  as  water.  Water 
of  crystallization  forms  a  part  of  crystals,  consti- 
tuting rocks  of  all  formations,  from  the  oldest  to 
the  most  recent.  Hydrogen  is  one  of  the  essen- 
tial constituents  of  all  animal  and  vegetable  mat- 
ter. It  is  also  found  pure.  Whatever  decompo- 
ses water  by  attracting  and  uniting  with  its  oxy- 
gen, disengages  the  hydrogen  in  an  uncombined 
state.  It  appears  also,  as  a  production  of  nature, 
in  the  state  of  several  compound  gases  ;  such  as 
the  sulphuretted  hydrogen,  a  very  nauseous  scen- 
ted gas,  the  carburetted  hydrogen,  which  issues 
from  decaying  vegetables  and  coal  mines,  &c.  It 
issues  from  decaying  animal  matter  in  combina- 
tion with  nitrogen,  forming  ammonia. 

Prop.  t.  Hydrogen  and  oxygen  being  the  com- 
bined constituents  forming  water,  if  the  oxygen  of 
the  water  is  united  to  a  n,etal  by  elective  affinity? 
the  hydrogen  will  come  over  in  the  state  of  gas. 

Illustration.  Put  half  a  gill  of  water  into  a 
pint  retort,  to  be  decomposed.  Put  into  the  water 
a  table  spoonfull  of  iron  filings,  or  half  as  much 
zinc,  hydrogen  would  come  over,  after  a  long  time> 
in  small  quantities.  As  this  operation  would  re- 
quire several  months,  put  in  diluted  sulphuric 
acid,  consisting  of  a  wine  glass  one  third  full  of 
sulphuric  acid,  filled  up  with  water,  to  hasten  the 


70  CLASS   III.      OXIDABLES. 

process.  Hydrogen  gas  will  come  over  immedi- 
ately and  with  great  rapidity.  If  a  smaller  pro- 
portion of  sulphuric  acid  be  put  in,  the  gas  will 
come  over  slower  and  continue  longer.  It  may  be 
received  over  water  in  bell-glasses,  tumblers,  gas- 
holders, decanters,  &c. 

The  sulphuric  acid  may  be  dispensed  with,  if 
the  water  be  converted  into  steam  and  pass  over 
hot  iron.  This  may  be  performed  by  passing  an 
open  gun-barrel  across  a  furnace  and  heating  it 
red  hot  ;  while  water  is  boiling  at  the  lower  end 
in  a  tin  cap,  box,  or  glass  retort  with  a  neck  fitted 
to  the  gun- barrel.  Iron  filings  or  wire  may  be  put 
into  the  gun-barrel  ;  but  the  heated  inner  surface 
of  a  new  barrel  will  decompose  the  water,  without 
the  filings  or  wire,  for  a  short  time. 

Rationale.  The  oxygen  of  water  has  a  strong- 
er affinity  for  iron  than  for  hydrogen,  consequent- 
ly elects  the  iron  and  excludes  the  hydrogen. 
And  though  the  hydrogen  is  in  a  liquid  state  when 
combined  with  oxygen,  it  takes  so  much  caloric 
when  in  a  free  state  as  to  become  a  gas.  It  is  not 
known  how  the  sulphuric  acid  acts  upon  the  iron 
or  upon  the  water  in  so  rapidly  hastening  the  pro- 
cess of  decomposition.  We  can  say,  that  in  a 
manner  not  yet  explained,  it  excites  a  strong  pre- 
disposition in  the  iron  and  oxygen  to  unite.  As 
muriatic  acid  produces  the  same  effect,  it  cannot 
be  ascribed  to  any  decomposition  of  the  acid,  as 
suggested  by  Dr.  Cox  ;  for  muriatic  acid  cannot 
be  decomposed — at  least  so  as  to  separate  oxygen 
from  a  base. 

Application.     Earthquakes- are  probably  caus- 
ed by  hydrogen  in  some  instances  ;  but  more  fre 
(jiie&tlv  by  sulphuretted  hydrogen.    Iron  and  wa 


PRINCIPLE    1.      HYDBOGEST.  71 

t 

ter  are  in  contact  in  the  earth,  consequently  hy- 
drogen is  formed.  The  hydrogen  passes  into  vast 
caverns  and  mixes  with  air.  Any  spontaneous 
combustion  in  the  earth,  for  which  there  are  many 
causes,  would  explode  the  gas  ;  which  explosion, 
if  of  sufficient  extent,  would  cause  an  earthquake. 
Prop.  2.  Hydrogen  gas  burns  in  a  continued 
Maze,  when  passed  from  any  vessel  into  atmos- 
pheric air. 

Illustration.  Put  some  of  the  gas  into  a  tubu- 
lated bell-glass  or  common  gas-holder,  and  im- 
merse it  beneath  the  surface  of  the  water  in  the 
cistern  ;  having  previously  fitted  a  pipes  tern  into 
a  cork  with  which  the  tubulature  or  hivie  in  the  top 
of  the  gas-holder,  is  stopped,  the  upper  end  of  the 
pipestem  being  also  stopped  with  a  peg.  Pull  out 
the  peg,  and  at  the  same  instant  apply  a  candle  to 
the  stream  of  hydrogen  which  is  forced  out  by  the 
pressure  of  the  water,  and  it  will  be  lighted  and 
burn  steadily  with  some  degree  of  decripitation. 
If  a  stop  cock  be  used,  which  is  better,  no  peg  will 
be  wanted  in  the  end  of  the  pipe. 

Rationale,  The  hydrogen,  and  oxygen  of  the 
atmosphere  unite  and  form  water.  Caloric  is  then 
forced  out,  as  explained  under  caloric  at  the  15th 
proposition. 

Application.  This  flame  was  formerly  called 
the  philosophic  candle  ;  though  it  was  exhibited 
in  a  very  simple  manner.  It  does  not  give  so 
much  light  as  some  of  its  compounds,  and  is  not 
now  used  for  gas  lights. 

Prop.  3.  Hydrogen  gas  explodes  if  inflamed 
when  intermixed  with  oxygen — very  violently  if 
the  oxygen  is  pure,  considerably  when  the  oxygen 
is  combined  with  nitrogen  as  in  atmospheric  air. 


72  CLASS    III.      OXIDABLES. 

Illustration.  Mix  a  quantity  of  hydrogen  and 
atmospheric  air  in  a  tumbler  or  small  bell-glass, 
one  part  of  hydrogen  to  two  of  air  by  bulk.  Fill 
the  gas-pistol  with  water,  hold  the  thumb  on  the 
vent  hole,  or  stop  it  with  a  peg,  and  set  the  mouth 
over  one  of  the  funnel  holes  in  the  shelf.  Pour 
under  and  fill  the  gas-pistol  with  the  mixture  of 
air  and  hydrogen.  Having  a  suitable  cork  ready 
and  well  soaked  in  water,  stop  the  mouth  of  the 
pistol  very  tight  with  it.  Now  raise  up  the  pistol, 
elevating  the  mouth  so  as  to  point  above  the  heads 
of  the  class ;  remove  the  thumb  from  the  vent,  and 
at  the  same  instant  touch  the  flame  of  a  candle  to 
it.  It  will  explode  and  drive  the  cork  to  a  distance. 
But  if  the  mixture  be  made  of  equal  parts  of  pure 
oxygen  and  hydrogen,  the  explosion  will  be  much 
more  violent. 

.Rationale.  During  the  explosion,  the  two  gas- 
es combine  and  form  water.  As  the  volume  of  wa- 
ter is  much  smaller  than  the  volume  of  the  gases, 
a  question  naturally  arises,  why  is  not  the  cork 
driven  into  the  pistol  instead  of  being  driven  out 
with  such  force  ?  If  the  two  gases  united  instan- 
taneously throughout  the  whole  pistol,  the  cork 
would  be  pressed  inwards.  But  their  combina- 
tion is  progressive,  from  the  vent  hole  to  the  muz- 
zle ;  and  the  heat,  consequently  the  expansion  of 
the  uncombined  gases,  outruns  the  process  of  com- 
bination. 

Application.  This  exhibits  the  principle  of 
earthquakes  before  referred  to.  Also  the  inflam- 
mability of  hydrogen,  and  shows  that  oxygen  is  a 
supporter  of  combustion. 

Prop.  4.  Hydrogen  gas,  though  itself  combus- 
tible,  will  not  support  the  combustion  of  other  sub~ 
stances. 


PRINCIPLE   1.       HYDllOGEN.  73 

Illustration.  Fill  a  glass  cylinder,  or  opodel- 
doc vial,  with  hydrogen  gas.  Raise  it  up  slowly, 
still  retaining  it  in  its  inverted  position,  and  care- 
fully settle  it  down  over  a  candle.  When  the  gas 
touches  the  flame  it  will  slightly  explode.  After 
it  is  so  far  settled  down  over  the  candle  as  to  bring 
the  wick  within  the  gas,  it  will  be  extinguished. 

Rationale.  The  vessel  containing  the  gas  is  rais- 
ed with  the  closed  end  upwards,  because  the  gas 
is  much  lighter  than  atmospheric  air.  The  slight 
explosion  at  the  mouth  of  the  vessel  occurs  in 
consequence  of  the  mixture  of  the  hydrogen  at  the 
mouth  with  the  oxygen  of  the  atmosphere. 

Application.  The  distinction  between  a  com- 
bustible substance  and  a  supporter  of  combustion, 
should  be  well  settled  in  the  mind  of  the  student. 
Hydrogen  and  oxygen  are  good  specimens. 

Prop.  5.  Hydrogen  and  oxygen,  when  unite  A 
by  combustion,  form  water. 

Illustration.  Fit  a  stop-cock  into  the  top  of  a 
•wooden  gas-holder  or  tubulated  bell-glass.  To 
the  upper  end  of  the  stop- cock  fit  a  lead  pipe  about 
one  inch  and  a  half  in  length.  Cut  off  a  wine- 
glass, with  a  triangular  file,  so  far  above  the  bot- 
tom as  to  leave  a  hole  equal  to  the  size  of  the  lead 
tube.  Fit  the  glass  so  that  it  may  stand  upon  the 
upper  end  of  the  stop-cock  with  the  lead  tube  ex- 
tending into  it  through  the  hole  in  the  bottom. 
The  glass  is  to  be  half  full  of  mercury  when  used. 
Fit  a  pipe  stem  into  the  end  of  the  leaden  pipe,  so 
that  it  shall  stand  upright  through  the  mercury  to 
the  height  of  about  two  inches  above  it.  Having 
put  a  sufficient  quantity  of  hydrogen  into  the  gas- 
holder, turn  the  stop  and  let  a  small  quantity  of 

7 


74  CLASS    III.       OXIDABLES. 

the  gas  pass  out,  which  iliust  be  lighted  up  by  ap 
plying  a  candle  to  the  end  of  the  pipe  stem.    Re- 
gulate the  blaze  by  the  stop,  making  it  as  small 
as  it  will  burn.     But  if  the  blaze  is  extremely 
small,  it  will  not  burn  in  the  oxygen. 

Having  previously  filled  entirely  full  a  perfect- 
ly dry  8  ounce  vial  with  oxygen,  stop  it  with  the 
finger  and  raise  it  up  and  shut  it  down  suddenly 
over  the  burning  hydrogen,  bringing  its  mouth 
do  vn  to  the  mercury.  It  will  continue  to  burn, 
but  will  not  explode.  At  length  the  blaze  will 
become  broader,  and  finally  cease.  At  that  instant 
turn  the  stop.  On  examination  the  vial  will  be 
found  to  be  lined  with  fine  drops  of  water,  and 
some  will  run  down  upon  the  mercury.  No  at- 
mospheric air  will  unite  with  the  oxygen ;  because, 
as  soon  as  the  blaze  comes  within  the  oxygen  gas 
it  will  expand  with  the  heat,  and  thus  it  will  be 
partly  forced  out  while  the  vial  is  settling  down 
towards  the  mercury,  and  of  course  prevent  the 
entrance  of  air. 

The  best  method  for  filling  the  vial  with  oxygen 
so  as  to  keep  it  dry,  is,  to  fill  it  from  a  bladder,  or 
from  a  tubulated  bell-glass  immersed  in  the  cis- 
tern. Iii-  either  case,  let  the  vial  stand  upright, 
and  force  the  oxygen  to  the  bottom  of  it  by  ex- 
tending the  tube  to  the  bottom.  Force  in  about 
thrice  as  much  oxygen  as  would  be  sufficient  to 
fill  the  vial,  which  will  entirely  clear  it  from  at- 
mospheric air. 

Rationale.  By  this  mode  of  burning  the  two 
gases,  every  thing  is  excluded  which  can  possibly 
affect  the  new  compound.  It  follows  that  water 
is  formed,  in  the  state  of  vapour,  in  this  case,  by 
the  combustion  and  consequent  couibination  of 
oxygen  and  hydrogen. 


PRINCIPLE    i.       HYDROGEX,  75 


tion.  From  this  experiment  it  appears, 
that  the  burning  of  one  of  the  most  combustible 
substances  with  the  all  pov^erflll  supporter  of  com- 
bustion, the  liquid  is  produced  which  we  apply 
to  extinguish  flame.  Attempts  have  been  made  to 
decompose  water  with  charcoal,  so  that  a  perpet- 
ual supply  of  hydrogen  may  be  added  as  a  fuel. 

Prop.  6.  While  hydrogen  is  burning  in  oxy- 
gen, it  excites  vibrations  in  a  glass  vessel,  pro 
ducing  sounds. 

Illustration.  While  the  above  apparatus  re- 
mains unmoved,  li^ht  up  the  hydrogen  as  before, 
take  up  a  small  decanter  of  oxygen  which  was 
filled  in  the  cistern,  stopping  its  mouth,  quickly 
shut  it  down  over  the  burning  hydrogen  so  as  to 
bring  the  mouth  very  near  the  mercury,  but  not 
quite  touch  it.  The  decanter  will  immediately 
commence  ringing,  and  if  every  thing  is  conduct- 
ed judiciously,  with  a  suitable  glass,,  &c.  the 
sound  will  almost  deafen  all  present.  I  think  the 
common  bottles  used  for  preserving  citrons  and 
other  sweet- meats,  is  the  best  form.  In  thfcse  the 
neck  is  broad  and  about  one  third  the  length  of 
the  body. 

Keeping  the  flame  chiefly  in  the  neck,  while 
the  tip  of  the  flame  ascends  beyond  the  shoulder 
into  the  broadest  part,  produces  a  greater  effect. 
When  the  sound  grows  faint, turn  the  stop  a  little, 
so  as  to  enlarge  the  stream  of  hydrogen,  or  fill  the 
jar  again  with  oxygen. 

Rationale.  The  most  reasonable  explanation 
given  for  these  vibrations  appears  to  be  5  that  the 
succession  of  globules  of  water,  which  are  formed, 
strike  against  the  sides  of  the  glass,  with  such 
force  as  to  cause  the  ringing.  By  suspending 


CLASS    III.       OXIDABLES, 

fine  asbestos  threads  within  the  vessel,  it  may  be 
seen  that  these  globules  do  move  with  much  ve- 
locity. 

Application.  Whatever  hypothesis  we  may 
choose  to  adopt,  the  doctrine  of  sound,  as  produced 
by  the  vibration  of  elastic  bodies,  is  well  illustrat- 
ed by  this  experiment.  A  very  amusing  musical 
instrument  might  be  constructed,  by  suspending 
different  sized  glass  vessels  over  a  horizontal 
tube,  with  lateral  keyed  outlets,  passing  into  the 
vessels. 

Prop.  7.  Hydrogen  is  much  lighter  than  at- 
mospheric air. 

Illustration.  Fit  a  tobacco  pipe  to  the  end  of 
a  flexible  tube.  Attach  the  tube  to  a  stop-cock 
which  is  fitted  to  the  top  of  a  gas-holder.  Set  a 
bowl  of  strong  soap  suds  on  a  table  near  the  cis- 
tern. Having  put  a  large  quantity  of  hydrogen 
into  the  gas-holder,  turn  the  stop  so  as  to  let  out 
xlie  gas  slowly.  By  applying  the  pipe  bowl  to 
the  soap  suds,  bubbles  may  be  inflated  with  the 
Lydrogen  gas  and  shaken  off,  as  children  inflate 
them  with  their  breath  and  throw  them.  But  in- 
stead of  falling  downward  as  when  inflated  with 
the  breath,  they  will  ascend  and  rise  to  the  upper 
ceiling. 

Rationale.  The  soap  suds  being  an  adhesive 
liquid,  is  blown  into  bubbles  by  the  stream  of  hy- 
drogen gas  which  is  forced  into  it  by  the  pressure 
of  water  in  the  cistern.  When  the  bubble  attains 
to  such  a  size  that  the  difference  between  the 
weight  of  the  hydrogen  gas  and  the  atmospheric 
air  is  sufficient  to  overcome  the  weight  of  the  soap 
suds  employed  in  making  the  bubble,  it  ascends, 


PRINCIPLE    1.       HYDROGEN*  77 

Application.  This  is  the  gas  with  which  bal 
loons  are  inflated.  It  being  but  about  a  thirteenth 
as  heavy  as  atmospheric  air,  a  large  balloon, 
when  inflated  with  it,  will  carry  up  several  per 
sons. 

Prop.  8.  Water  absorbs  and  holds  in  combina- 
tion a  quantity  of  atmospheric  air. 

Illustration.  Fill  the  bulb  and  part  of  the  neck 
of  a  bolthead,  or  a  florence  flask  may  do,  with 
river  water,  or  any  water  which  has  been  consid- 
erably agitated  in  the  open  air.  Tie  a  thread 
around  the  ueck  at  the  precise  surface  of  the  wa- 
ter. Now  suspend  it  over  a  candle,  or  over  burn- 
ing coals,  and  the  water  will  rise  in  the  neck. 
Let  the  heat  be  continued  a  little  while,  but  not  so 
as  to  commence  boiling,  and  numerous  bubbles  of 
air  will  be  disengaged  and  appear  in  the  vessel. 

Rationale.  T*he  particles  of  atmospheric  air, 
which  are  in  water,  are  too  minute  to  be  visible. 
But  on  being  heated  their  volumes  become  enlarg- 
ed, as  explained  in  the  6th  Prop,  under  Caloric. 

Application.  Air  gives  to  water  in  running 
streams  a  kind  of  briskness,  as  it  is  commonly  call- 
ed, which  is  not  found  in  the  water  of  wells  ;  and 
on  agitating  well  water  a  short  time  in  open  air  it 
is  greatly  improved  for  drinking.  The  air  con- 
tained in  water  is  essential  to  the  lives  of  fish, 
which  has  been  often  shewn  by  experiment. — 
Some  species  of  fish  cannot  live  in  a  small  still 
fish  pond,  which  would  be  healthy  if  the  water 
was  frequently  agitated,  so  as  to  give  it  a  better 
opportunity  to  absorb  air. 

A  remarkable  fact,  which  is  asserted  by  the 
raftsmen  on  the  Hudson  river  above  the  head  of 

7.* 


78  CLASS   III.      OXIDABLES. 

tide  water,  requires  particular  investigation, 
They  assert,  that  their  mouths  become  sore,  and 
a  sensation  is  experienced  as  after  a  long  continued 
use  of  vinegar  ari^l  water,  whenever  they  practice 
drinking  the  water  of  the  river.  It  should  be  added, 
that  in  this  part  of  the  river  the  water  is  much 
agitated  in  the  rafting  season,  which  is  the  spring. 

Prop .  9.  Water  on  freezing  expands  its  vol- 
ume and  thereby  diminishes  its  specific  gravity. 

Illustration.  Lay  a  piece  of  ice  on  water  and  it 
will  float.  Glass  vessels  are  broken  in  wMch  wa- 
ter is  left  to  freeze,  unless  they  diverge  upwards 
so  much  as  to  allow  the  ice  to  rise  up  when  the 
freezing  process  commences. 

Rationale.  By  an  effort  to  shoot  into  crystals, 
probably  very  minute  interstices  are  formed  in  the 
ice.  la  addition  to  this,  when  the  water  becomes 
solid,  caloric  is  pressed  out  anoV  enters  the  minute 
particles  of  air  contained  in  the  water  and  enlarg- 
es their  volume,  as  explained  under  the  6th  and 
14th  Prop,  of  Caloric.  If  this  hypothesis  is  not 
demonstrated,  it  is  better  to  adopt  it  for  the  pre- 
sent, than  to  substitute  an  anomaly  by  saying 
water  is  an  exception  to  the  general  law. 

Application.  To  this  principle  we  are  indebt- 
ed for  our  bridges,  erected  by  nature  for  the  bois- 
terous season  of  winter.  Thus  too  rocks  are  split 
down  and  broken  into  soils. 

Prop.  10.  The  specific  gravity  of  water  is  en- 
creased  by  dissolving  a  salt  in  it. 

Illustration.  Fill  two  tumblers  almost  fall  of 
water.  Let  the  water  of  one  tumbler  be  pure,  and 
that  of  the  other  contain  as  much  common  salt  as 
it  will  hold  at  the  temperature  of  pretty  cool  wa« 


PBINCIPLE    2.       NITROGEN.  79 

ter.  Attach  a  piece  of  lead  to  a  small  block  of 
wood,  whittling  off  from  either  the  lead  or  the 
wood  until  it  will  barely  float  in  the  tumbler  of 
salt  water.  Now  put  it  into  the  tumbler  of  fresh 
water  and  it  will  sink  to  the  bottom. 

Rationale.  Salt  being  strongly  attracted  by 
water,  combines  with  it  closely,  and  probably 
enters  the  interstices  between  its  particles,  giving 
it  a  more  dense  consistency?  of  course  greater  spe- 
cific gravity. 

Application.  A  ship  will  swim  in  the  ocean 
with  a  freight  so  heavy,  that  it  would  sink  if  sail- 
ed into  a  fresh  water  river.  Persons  cast  away 
at  sea  can  sw;im  much  easier  than  they  could  in 
fresh  water,  because  the  greater  specific  gravity 
of  the  water  will  help  to  buoy  them  up. 

NITROGEN.^ 

Natural  History  and  general  Remarks. 

Nitrogen  is  one  of  the  two  constituents  of  the 
atmosphere  ;  composing  about  79  per  cent  of  it. 
Nitrogen  and  oxygen  are  the  only  essential  con- 
stituents of  the  atmosphere  ;  though  other  gases, 
as  well  as  aqueous  vapour,  are  always  suspended 
in  it.  It  may  be  easily  divested  of  these  substan- 
ces by  operating  upon  an  enclosed  portion  of  it  5 
and  then  only  it  ma;  be  called  pure  atmospheric 
air.  Some  authors  have  set  down  aqueous  vapour 
and  carbonic  acid  as  constituent  parts  of  the  at- 
mosphere. But  I  can  perceive  no  better  reason 
for  treating  them  as  essential  constituents  of  tho 
atmosphere,  than  for  treating  carburetted  hydro- 

*  I  am  very  elad  to  find  nitrogen  used  by  Brando  instead  of 
^Vhich  Gorhanjijas  very  unadvisedly  adopted. 


80  CLASS    III.       OXIDABLES. 

gen,  ammonia,  or  floating  dust,  as  such.  Or  for 
treating  mud  and  drift-wood  as  essential  constitu- 
ents of  the  Hudson,  or  of  the  Thames. 

Nitrogen  is  an  essential  constituent  of  saltpetre, 
from  which  it  derived  its  name.  It  is  also  produc- 
ed in  a  pure  state  from  the  earth  at  New-Leba- 
non Springs  and  in  Hosick,  in  the  state  of  New- 
York.  See  Prop.  4,  under  this  head. 

Prop.  1.  Nitrogen  and  oxygen  being  the  only 
essential  constituents  of  atmospheric  air,  if  the 
oxygen  be  abstracted  from  an  enclosed  portion  of 
the  atmosphere,  the  nitrogen  will  be  left  in  the  state 
of  gas. 

Illustration.  The  oxygen  may  be-extracted  by 
burning  phosphorus  in  an  enclosed  portion  of  at- 
mospheric air ;  or  more  perfectly  if  the  season 
is  not  cold,  as  follows :  Mix  finely  pulverised 
sulphur  and  iron  filings,  rubbing  them  well  to- 
gether. Then  moisten  the  mixture  with  water, 
and  place  as  much  of  it  on  the  bottom  of  an  invert- 
ed wine-glass  as  will  lie  on  it,  or  place  it  on  any 
other  stand  of  about  the  same  height.  Place  this 
on  a  shelf  of  the  cistern,  or  in  a  large  soup  plate 
filled  with  water.  Now  shut  over  this  mixture  a  half 
gallon  bell-glass,  or  specie  bottle  of  that  size,  and 
let  it  stand  about  twenty- four  hours.  The  oxy- 
gen will  be  absorbed  from  the  air  in  the  bell-glass, 
and  the  water  will  have  ascended  to  fill  the  vacan- 
cy made  by  the  loss  of  the  oxygen,  which  is  about 
twenty-one  per  cent.  The  remaining  gas  will  be 
nitrogen. 

Rationale.  Phosphorus  attracts  oxygen  so 
strongly  that  its  combustion  will  continue  until 
very  nearly  the  last  atom  of  oxygen  is  exhausted, 
paste  of  iron  filings  and  sulphur,  however^ 


PRINCIPLE  2.      NITROGEN.  81 

will  absorb,   probably,  the  very  last  atom.     But 
the  process  is  slow  and  difficult  to  be  explained. 

Application.  Whatever  .consumes  the  oxygen 
of  the  air  in  a  close  room,  will  tend  to  leave  an 
encreased  proportion  of  nitrogen.  Probably  the 
prisoners  crowded  into  the  Black  Hole  of  Cal- 
cutta, had  but  very  little  oxygen  to  breathe  for 
some  time  before  they  died. 

Prop.  2.  Nitrogen  gas  extinguishes  flame  and 
destroys  life,  if  breathed,  by  excluding  oxygen. 

Illustration.  Immerse  a  burning  candle  in  an 
8  ounce  vial  of  it,  it  will  be  extinguished.  Fill  a 
small  jar  or  large  mouth  vial  entirely  full  of  the 
gas,  and  turn  it  up.  Take  a  live  mouse  into  the 
hand,  having  a  leathern  glove  on  it  to  defend  it 
from  the  bite  of  the  mouse,  and  drop  it  into  the 
jar,  instantly  covering  it  again.  The  mouse  will 
expire  in  a  short  time,  though  not  so  soon  as  in 
some  other  gases. 

Rationale.  The  candle  is  extinguished  and 
the  mouse  is  killed,  by  excluding  oxygen  ,  which 
is  essential  to  the  support  of  combustion  and  of 
life.  But  this  gas  does  not  operate  as  an  active 
agent  in  the  destruction  of  life,  like  carbonic  acid 
gas. 

Application.  Since  oxygen  and  nitrogen  arc 
the  only  essential  constituents  of  the  atmosphere, 
and  since  nitrogen  entinguishes  flame  and  destroys 
life,  it  is  manifest  that  oxygen  is  the  only  support- 
er of  combustion  and  animal  respiration  in  the 
atmosphere. 

Prop.  3.  Nitrogen  gas  is  the  lightest  of  the 
constituents  of  atmospheric  air. 

Illustration.     Extinuish  a  candle  as  before 


82  CLASS    III.      OXIDABLES. 

directed  in  a  vial  of  nitrogen  gas.  Then  cover  it 
loosely  with  dry  paste-board,  so  that  the  motion 
of  the  air  may  not  drire  it  out,  and  let  it  stand  a 
while.  Afterwards,  or  at  least  after  a  few  trials, 
the  candle  will  not  be  extinguished. 

Rationale.  Nitrogen,  being  lighter  than  the 
atmospheric  air,  ascends  like  all  lighter  bodies 
when  immersed  in  heavier  liquids  or  gases  ;  while 
common  air  takes  its  place  in  the  vial. 

Application.  Though  oxygen  and  nitrogen  in 
open  space,  mix  in  an  equilibrium  proportion  ; 
when  one  of  them  is  in  excess,  or  in  any  .manner 
separated  from  its  state  of  union,  it  will  seek  its 
place  according  to  its  specific  gravity.  Conse 
quently  a  disunited  quantity  of  oxygen  will  settle 
downwards,  and  that  of  nitrogen  will  ascend.  So 
that  when  much  oxygen  is  consumed  by  a  crowd 
of  persons  in  a  close  room,  the  excess  of  nitrogen 
will  ascend  and  render  the  air  near  the  upper 
ceiling  very  unfit  for  breathing,  while  the  air 
lower  down  is  more  suitable  for  respiration. 

Prop.  4.  Mout  seventy-nine  per  cent  of  nitro- 
gen gas  mixed  with  twenty-one  per  cent  of  oxy- 
gen, will  form  artificial  air,  in  all  respects  similar 
to  atmospheric  air. 

Illustration.  Take  four  8  ounce  vials,  as  near 
ly  equal  in  size  and  form  as  can  be  procured,  and 
fill  them  as  follows  :  The  first  with  nitrogen,  the 
second  with  oxygen,  the  third  with  four  measures 
of  nitrogen  and  one  measure  of  oxygen,  and  lei 
the  fourth  remain  with  atmospheric  air.  Turn 
them  all  up,  leaving  them  covered  with  pieces  of 
wet  paste-board,  excepting  the  fourth  which  may 
be  open.  Light  a  short  piece  of  wax  taper  which 
is  suspended  by  a  wire  coiled  round  at  its  lower 


PRINCIPLE    2.       NITROGEN.  83 

end.  Let  it  burn  some  time  with  a  large  wick, 
which  should  he  spread  out  wide  and  fnll  of 
sparks.  Now  immerse  the  blazing  caudle  in  the 
nitrogen,  and  it  will  be  extinguished — then  quick- 
ly immerse  it  in  the  oxygen  and  it  will  be  re-light- 
ed— next  immerse  it  alternately  several  times  in 
the  cylinders  of  artificial  and  natural  air,  and  it 
will  burn  alike  in  both. 

Rationale.  The  wick  of  the  candle  is  not  act- 
ed on  positively  by  the  nitrogen  ;  but  stops  burn- 
ing merely  on  account  of  the  exclusion  of  oxygen. 
It  therefore  remains  sufficiently  heated  to  contin- 
ue the  flame,  as  soon  as  it  receives  a  supply  of 
pure  oxygen.  As  the  candle  burns  in  the  artifi  • 
cial  air  just  as  it  does  in  the  natural,  it  is  manifest 
that  the  natural  and  artificial  are  similar ;  at  least 
so  far  as  respects  combustion.  Since  the  appear- 
ance oft  burning  candle  is  different,  when  confin- 
ed in  a  vial,  from  its  appearance  in  open  air,  it  is 
necessary  to  immerse  it  in  a  vial  of  natural  air 
when  comparing  with  its  appearance  in  artificial 
air. 

Application.  By  this  experiment  we  see  at  one 
view  the  nature  of  the  two  constituents  of  the  air 
in  their  separate  and  in  their  combined  state. 
Though  these  proportions  are  temporarily' varied 
in  the  atmosphere  of  confined  rooms,  and  some- 
times in  large  cities  and  other  places,  nature  has 
provided  remedies  for  such  contingencies.  A  con- 
siderable supply  of  oxygen  is  drawn  from  the  ve- 
getable kingdom,  which  was  illustrated  under 
oxygen.  There  are  other  means  prescribed  for 
equalizing  the  proportions  of  those  gases,  accord- 
ing to  their  equilibrium  principle. 

The  production  of  the  nitrogen  cannot  always 


84  CLASS    III.       OXIDABLES. 

be  accounted  for.  There  is  a  small  hill  or  rather 
an  ascent  of  ground  in  the  town  of  Hosick,  in  the 
state  of  New- York,  from  which  continually  issues 
immense  quantities  of  nitrogen  gas.  Wherever 
the  little  rivulets  pass  over  any  part  of  four  or  five 
acres  of  this  hill,  nitrogen  gas  continually  bub- 
bles through  the  water.* 

Prop.  5.  Atmospheric  air  holds  in  suspension 
more  or  less  of  aqueous  vapour. 

Illustration.  Put  a  little  common  table  salt 
into  a  wine-glass,  and  pour  on  it  strong  sulphuric 
acid  sufficient  to  wet  it.  Muriatic  acid  gas  will 
be  disengaged,  and  condense  aqueous  vapour  so  as 
to  become  visible,  and  appear  like  steam. 

Rationale.  Muriatic  acid  is  invisible,  as  shewn 
under  chlorine  ;  where  it  was  also  shewn,  that  it 
strongly  attracts  water.  When  discharged  into 
the  atmosphere,  its  attraction  for  water  brings 
together  numerous  invisible  particles  of  vapour, 
which  becomes  a  visible  vapour  when  thus  aggre- 
gated. 

Application.  This  experiment  demonstrates, 
that  clouds  are  not  the  only  repositories  of  aque- 
ous vapour  in  the  atmosphere  ;  but  that  it  is  held 
in  suspension  in  its  most  clear  and  transparent 
state. 

Prop.  6.  Nitrogen  is  found  combined  with  its 
highest  2^' oportion  of  oxygen  in  the  saltpetre,  from 
which  it  may  be  obtained  by  elective  affinity. 

Illustration.  Put  into  a  tubulated  pint  retort 
about  a  wine-glass  full  of  pulverized  saltpetre, 

*  Dr.  L.  C.  Beck  and  myself  collected  and  tested  this  gas  on  the  17th 
of  Aug.  1821.  It  is  situated  near  the  east  boundary  of  the  state  of  N. 
York,  about  6  miles  S.  W.  from  Bennington,  Vt.  Vid.  Report  of  the 
Geological  Strfvey  of  Rensselaer  county,  p.  29. 


PRINCIPLE}    2.       NITROGEX,  85 

and  pour  upon  it,  through  the  tubulature,  strong 
sulphuric  acid  sufficient  to  wet  it,  or  about  two 
thirds  as  much  by  weight  as  there  is  of  the  salt- 
petre. Having  previously  luted  the  neck  of  the 
retort  into  a  receiver  containing  a  gill  of  water 
which  has  a  stoppered  tubulature  ;  now  set  the 
retort  into  a  lead  pot  with  coals  and  raise  the  heal: 
very  moderately.  Leave  out  the  stopper  a  while, 
for  the  air  to  pass  out.  Then  put  in  the  stopper 
rather  loosely,  but  regulate  it  according  to  the 
pressure  of  the  gas.  The  nitric  acid,  (aqua  fortis) 
will  come  over  in  the  state  of  gas,  or  rather  in  con- 
nexion with  the  vapour  of  water.  It  will  be  ab 
sorbecl  by  the  water  of  the  receiver.  After  the 
process  is  finished,  pass  around  some  of  the  acid 
in  wine  glasses  with  a  rod,  and  the  class  will  re- 
cognize the  taste  of  diluted  aqua  fortis,  or  nitric- 
acid. 

Rationale.  Saltpetre  consists  of  nitric  acid  and 
potash.  Potash  has  a  stronger  affinity  for  sul- 
phuric than  for  nitric  acid.  Of  course  it  elects 
the  sulphuric  and  excludes  the  nitric.  Such  is  the 
nature  of  nitric  acid,  that  at  the  common  tempera- 
ture it  takes  to  itself,  from  the  surrounding  bodies* 
a  sufficient  quantity  of  caloric  to  become  a  gas  or 
vapour. 

Application.     On  this  principle  the  aqua  fortiy 
of  the  shops  is  manufactured.     Iron  retorts  are- 
used  in  the  manufacture  of  it  in  the  large  way  \ 
therefore  it  will  generally  give  the  test  of  iron 
with  prussic  acid.     As  saltpetre  always  contains 
muriate  of  soda,   muriatic  acid  will  be  contained 
in  the  aqua  fortis  of  the  shops  ;  consequently  wil 
generally  dissolve  gold,  unless  it  is  removed  by 
nitrate  of  silver,  (lunar  caustic. 

8 


86  CLASS    III.      OXIDABLES. 

Hemark.  It  is  difficult  to  operate  upon  this 
acid,  while  uncombined  with  water  ;  as  it  cannot 
be  collected  over  water  or  mercury.  But  as  it  is 
more  than  twice  as  heavy  as  atmospheric  air,  it 
may  be  collected  in  a  dry  vial,  as  directed  for  mu- 
riatic acid  ga&. 

Prop.  7.  Nitric  acid  may  be  reduced  to  nitrous 
acid  and  nitric  oxid,  by  yielding  part  of  its  oxy- 
gen to  a  metal. 

Illustration.  Put  into  a  very  small  retort,  a  gill 
retort  is  best,  a  table  spoonful  of  copper  filings — • 
about  one  fourth  as  much  mercury  will  do,  but 
not  so  well.  Then  pour  into  it  about  two  spoon- 
fuls of  nitric  acid,  diluted  with  three  or  four  times 
as  much  water.  Put  the  beak  of  the  retort  into 
the  cistern  under  a  receiver,  and  apply  the  heat  of 
a  candle  or  a  pan  of  coals  to  the  retort.  The  heat 
must  be  uniformly  applied,  or  the  gas  may  be  a 
little  condensed  in  the  retort,  and  the  water  will 
rush  into  it.  The  gas  will  soon  come  over  ;  but 
the  first  will  be  mixed  with  atmospheric  air,  of  a 
reddish  colour,  and  should  be  allowed  to  escape 
through  the  water  of  the  cistern.  It  will  soon  pass 
Into  the  receiver  in  a  colourless  state.  This  gas 
Is  the  nitric  oxid,  or  the  deutoxid  of  nitrogen. 

After  a  sufficient  quantity  has  been  collected, 
fill  a  small  glass  cylinder  or  opodeldoc  vial,  half 
full  of  oxygen  (atmospheric  air  will  do)  and  then 
fill  it  up  with  nitric  oxid.  It  will  immediately 
take  another  portion  of  oxygen  and  become  ni- 
trous acid.  This  gas  is  readily  distinguished 
from  the  nitric  oxi(i  by  its  deep  orange  colour 
and  strong  attraction  for  water.  If  the  glass  cylin- 
der be  turned  up  and  a  burning  candle  be  immers- 


PRINCIPLE   2.       NITROGEN.  87 

ed  ill  it,  the  candle  will  continue  to  burn  with  con- 
siderable brilliancy. 

Rationale.  The  copper  filings  always  reduces 
the  acid  to  an  oxid  in  this  case.  But  such  is  the 
affinity  of  the  deutoxid  of  nitrogen  for  oxygen, 
that  it  passes  almost  instantaneously  through  the 
hyponitrous  to  the  nitrous  state — that  is,  it  be- 
comes the  onn^e  nitrous  gas,  which  is  rapidly  ab- 
sorbed by  water. 

Application.  In  this  experiment  we  begin  with 
the  highest  state  of  oxidation  which  nitrogen  is 
capable  of.  In  this  state  only  it  is  found  in  na- 
ture. We  then  obtain  the  lower  acids  and  the 
oxids.  In  the  manufacture  of  nitric  acid,  more 
or  less  of  this  acid  is  found  combined  with  it  It 
is  this  which  passes  off  in  fumes  on  unstopping  a 
bottle  of  nitric  acid  of  the  shops. 

Prop.  8.  Nitric  acid  may  be  reduced  to  nitrous 
oxid  (the  exhilirating  gas)  by  heating  it  when 
chemically  combined  with  ammonia. 

Illustration.  Prepare  the  salt  called  nitrate  of 
ammonia,  according  to  the  directions  to  he  given 
under  ammonia.  If  the  salt  is  prepared  in  crys- 
tals, let  them  be  melted  and  evaporated  to  a  dry 
powder  in  an  open  earthen  plate  with  a  slow  heat. 
JSut  it  is  much  better  to  evaporate  it  to  dryness, 
\vith  so  much  heat  as  to  prevent  crystallization. 
Put  the  salt  into  a  retort,  which  may  be  about  one 
fourth  part  filled.  Apply  a  lead  tube  to  the  beak 
of  the  retort  about  three  feet  long,  to  prevent  acci- 
dents, which  generally  happen  without  it,by  break- 
ing the  retort  with  water  when  highly  heated.  No 
luting  is  necessary,  wet  tow  or  flax  will  be  suffi- 
cient. Now  set  the  retort  into  a  lead  pot  with 


88  CLASS    III.       OXIDABLES. 

coals,  and  raise  the  heat  with  the  hand  bellows. 
After  the  salt  has  melted,  and  when  vapours  he- 
gin  to  appear  in  the  retort,  apply  the  beak  to  the 
cistern  under  the  receiver.  A  great  quantity  of 
the  gas  will  soon  come  over  :  and  it  will  continue 
until  all  the  salt,  or  nearly  all,  disappears. 

This  nitrous  oxid  gas  may  be  breathed  in  small 
quantities  by  the  members  of  the  class,  about  a 
pint  to  each,  without  injury.  It  will  exhiliarate 
slightly,  and  the  taste  is  sweetish  and  pleasant, 
If  breathed  in  large  quantities,  as  about  two  gal- 
lons at  once,  and  respired  a  dozen  times,  it  intoxi- 
cates and  suspends  the  power  of  reasoning.  It  is 
unquestionably  injurious  to  health  ;  but  being  gen 
erally  administered  to  the  young  and  healthy, 
they  endure  it,  mostly,  without  any  bad  conse- 
quences. Brande  says  it  cannot  be  breathed  with 
impunity.* 

A  burning  candle  let  down  into  this  gas  has  its 
flame  increased,  and  it  is  always  surrounded  with 
a  purplish  ring  or  halo. 

Rationale.  By  these  two  last  illustrations  it 
appears,  that  nitrogen  combines  with  oxygen  in 
five  definite  proportions.  And  that,  beginning 
with  the  highest  proportion  it  may  be  reduced 
to  the  other  four.  In  reducing  it  to  the  lowest 
state,  the  nitrous  oxid,  the  rationale  is  thus  given 
by  chemists.  The  nitrate  of  ammonia  consists  of 
nitric  acid  combined  with  ammonia  ;  and  am- 
monia is  a  compound  of  nitrogen  and  hydrogen. 
When  considerable  heat  is  applied  to  this  salt, 

•Several  persons  have  lately  employed  themselves  in  peddling  this 
gas  about  the  country,  who  call  their  vulgar  frolicks,  lectures  on  chem- 
istry. All  sensible  citizens  ought  to  discountenance  such  gross  out- 
rages upon  decency,  which  tend  to  reduce  the  science  to  the  level  of 
a  puppet-show. 


PRINCIPLE    2.      NITROGEN.  89 

the  hydrogen  of  the  ammonia  unites  with  the  high- 
est portion  of  the  oxygen  of  the  nitric  acid  and 
forms  water.  This  comes  over  in  the  state  of 
white  vapour,  which  appears  first.  The  nitric  is 
thus  reduced  to  a  lower  state  of  oxidation.  At 
the  same  time  the  nitrogen  of  the  ammonia  takes 
away  another  proportion  of  oxygen  and  becomes 
nitrous  oxid,  leaving  to  the  nitrogen  of  the  nitric 
acid  just  oxygen  enough  to  form  nitrous  oxid  also. 
Application.  This  gas  was  at  one  time  thought 
to  be  useful  in  medicine  ;  but  its  use  seems  now  to 
be  doubted.  The  experiment  is  instructive,  as  it 
presents  an  interesting  view  of  complicated  de- 
composition. 

Prop.  9.  Nitrogen  and  hydrogen  combined 
form  an  alkaline  compound  called  ammonia,  harts* 
horn,  or  volatile  alkali. 

Illustration.  Fill  a  florence  flask  with  nitro- 
gen. Pulverize  iron  filings  so  as  to  make  them 
almost  into  an  impalpable  powder.  Pour  a  small 
quantity  of  water  upon  them,  so  as  to  be  enabled 
to  make  them  adhere  in  the  form  of  little  balls, 
twice  or  thrice  the  size  of  peas.  Drop  about  a 
dozen  of  these  bails  into  the  flask— care  being 
taken  not  to  leave  the  flask  open  but  an  instaut  at 
a  time  when  dropping  in  the  balls  ;  as  the  nitro- 
gen will  ascend.  After  several  days  small  quan- 
tities of  ammonia  will  be  produced.  This  may 
barely  be  perceived  by  the  scent ;  but  if  muriatic 
acid  gas  be  passed  into  the  flask,  muriate  of  am- 
monia, or  sal  ammoniac,  will  be  formed  in  a  small 
quantity  and  adhere  to  the  side  of  the  flask. 

A  much  better  method  for  illustrating  this  pro- 
position is,  to  decompose  ammonia.  Make  holes 
&  little  below  the  middle  of  a  lead  pot  so  that  a 


90  CLASS    III,      OXIDABLES, 

long  tobacco  pipe  may  be  passed  through  it  in  the 
hottest  place.  Lute  a  small  retort  (a  florence  flask 
will  do)  to  one  end  of  the  pipe  containing  dry  lime 
and  sal  ammoniac.  To  the  other  end  attach  a 
leaden  pipe,  so  bent  as  to  enter  a  bowl  of  water. 
Raise  the  heat  in  the  lead  pot  till  the  tube  begins 
to  be  red.  Now  apply  a  candle  to  the  retort. 
Ammoniacal  gas  will  pass  into  the  heated  tube  and 
be  decomposed.  Hydrogen  and  nitrogen  gases 
will  pass  into  the  bowl  of  water  and  may  be  col- 
lected in  the  usual  way. 

Rationale.  When  hydrogen  and  nitrogen  are 
mixed,  having  been  previously  prepared,  they  will 
not  combine  to  form  ammonia.  But  if  hydrogen 
comes  in  contact  with  nearly  pure  nitrogen,  at  the 
instant  of  its  disengagement  from  the  oxygen  of 
the  water,  it  combines  with  it.  In  this  evanescent 
state  only,  it  seems  that  the  composition  can  be 
effected. 

The  last  experiment  merely  demonstrates,  that 
the  two  constituents  of  ammonia  will  separate  on 
being  heated. 

Application.  These  experiments  demonstrate 
the  compound  nature  of  ammonia.  But  as  am- 
monia is  produced  in  great  abundance  in  nature, 
and  has  most  of  its  properties  in  common  with  the 
alkalies,  it  will  be  treated  in  connexion  with  the 
other  alkalies,  whose  bases  are  metalloids. 

SULPHUR. 

Natural  History  and  general  Remarks. 

Sulphur  is  very  abundant  in  nature.  It  is  gen- 
erally found  in  combination  with  a  metal;  which 
is  called  a  sulphuret.  la  combination  with  iroB; 


PRINCIPLE   3.       SULPHUR,  91 

called  iroii  pyrites,  it  is  found  in  every  rock  from 
the  oldest  granite  to  the  most  recent  secondary 
rock.  From  its  combination  with  this  metal  and 
with  copper,  the  brimstone  of  the  shops  is  obtain- 
ed by  the  process  called  sublimation. 

It  is  found  in  combination  with  lead,  zinc,  sil- 
ver, mercury,  &c.  It  is  also  found  pure  in  Italy 
and  in  other  volcanic  districts. 

It  is  inflammable  and  electrical.  It  is  tasteless 
and  inodorous  when  pure ;  but  on  combining  with 
oxygen  by  combustion,  or  by  heat  or  warmth  be- 
low combustion,  it  gives  off  a  disgusting  odour  or 
suffocating  gas. 

It  crackles  by  the  warmth  of  the  hand.  It  may 
be  crystallized  by  melting,  and  then  by  pouring 
out  the  melted  interior  of  the  mass,  just  at  the  pre- 
cise time  the  exterior  is  beginning  to  be  covered 
with  an  incrustation,  by  cooling.  The  crystals 
are  acicular. 

Prop.  1.  Sulphur  on  being  in  flamed  in  atmos- 
pheric air,  will  unite  with  a  definite  proportion  of 
oxygen  and  form  sulphurous  acid  gas. 

Illustration.  Cover  the  bottom  of  a  small  plate 
a  quarter  of  an  inch  deep  with  water.  Put  a  small 
piece  of  common  brimstone  upon  a  sheet  iron 
bench  set  in  the  plate,  which  is  sufficiently  heated 
to  inflame  the  brimstone,  and  shut  over  it  a  tubu- 
lated bell-glass,  or  a  tumbler  with  a  hole  in  the 
bottom.  This  vessel  must  be  of  a  size  just  to  shut 
down  within  the  rim  of  the  plate.  At  first  take 
the  stopper  out  and  raise  the  bell  glass  a  little 
above  the  water,  to  give  passage  to  a  current  of 
air.  Regulate  this  by  the  progress  of  the  burning 
sulphur.  After  the  bell-glass  appears  well  filled 
a  white  vapour;  shut  it  down  close  and  tight- 


92  GLASS   III.      OX1DABLES* 

eu  the  stopper.  The  water  in  the  plate  \vill  ab- 
sorb the  sulphurous  acid  gas  in  about  five  minutes. 
Pour  part  of  this  water  into  wine  glasses  and  pass 
it  around,  and  the  class  will  perceive  the  nause- 
ous sulphurous  astringent  taste,  peculiar  to  this 
acid.  In  the  mean  time  wet  several  substances, 
coloured  with  vegetable  colouring  matter,  and  it 
will  extinguish  many  of  them,  but  not  all.  A  yel- 
low straw  braid  becomes  whitened  in  it  ;  and 
some  colours  on  calico  will  be  extinguished.  The 
liquid  sulphurous  acid  loses  this  property  by 
keeping  long. 

Rationale.  It  seems  that  though  sulphur  is 
highly  inflammable,  it  will  not  receive  its  highest 
proportion  of  oxygen  while  in  a  gaseous  state. 
For  if  burned  in  pure  oxygen,  sulphurous  acid 
will  be  produced.  VVrhen  colours  are  extinguish- 
ed by  sulphurous  acid,  it  is  decomposed.  From 
this  it  appears,  that  its  disengaged  oxygen  produ- 
ces the  effect,  like  the  oxygen  disengaged  when 
chlorine  is  reduced  to  muriatic  acid. 

Application.  This  acid  is  used  by  milliners 
both  in  the  liquid  and  in  the  gaseous  state,  for 
bleaching  straw  bonnets.  If  old  yellow  straw 
braid  is  soaked  a  while  in  water  and  then  suspend- 
ed inside  of  a  no- headed  barrel  or  hogshead,  and 
brimstone  is  inflamed  at  the  bottom  of  the  cask 
and  suffered  to  commence  burning  thoroughly, 
then  the  top  covered  over,  the  straw  will  soou 
become  whitened  by  the  action  of  this  acid.  It 
is  also  used  for  killing  bees  when  taking  up  a 
hive,  and  for  killing  insects  to  preserve  in  a  col- 
lection. 

Prop.  2.  Sulphur,  on  being inflamedin  atmos- 
pheric air?  jf  previously  pulverized  and  mixed  wiib 


PRINCIPLE    3.      SULPHUR.  93 

it  portion  of  saltpetre,  will  unite  with  its  highest 
definite  proportion  of  oxygen  and  form  sulphuric 
acid,  or  oil  of  vitriol. 

Illustration.  Dry  some  saltpetre  on  a  plate. 
Then  pulverize  it  very  thoroughly,  and  mix  it 
with  about  four  times  as  much  sulphur,  (in  the 
large  way,  eight  times  as  much  sulphur  is  used,) 
and  rub  them  intimately  together.  Now  proceed 
in  all  respects  as  in  producing  sulphurous  acid, 
above  described  ;  and  the  additional  portion  of 
oxygen  furnished  by  the  saltpetre  will  perfect  the 
process.  After  the  water  has  absorbed  the  acid, 
pass  some  of  it  around  in  wine  glasses  with  tasting 
rods,  and  the  class  will  recognize  the  clean  pleas- 
ant sour  taste  of  the  sulphuric  acid,  or  oil  of  vitriol, 
in  a  weak  or  diluted  state.  It  is  distinguished  from 
all  other  acids  by  its  charring  or  blackening 
vegetable  ^ubstances. 

Rationale.  Under  the  preceding  proposition 
the  sulphur  combines  with  the  proportion  of  oxy- 
gen requisite  for  producing  sulphurous  acid.  The 
saltpetre,  being  in  immediate  contact,  furnishes 
the  next  proportion  and  produces  the  sulphuric 
acid. 

Application.  The  oil  of  vitriol  of  the  shops  is 
made  on  the  same  principle.  Leaden  chambers 
being  substituted  for  the  bell-glass,  and  the  floor 
is  covered  with  water.  It  is  at  first  obtained  in  a 
very  diluted  state.  It  is  then  slowly  evaporated, 
until  it  comes  to  a  suitable  strength  for  the  market. 
When  this,  or  any  other  acid,  is  combined  with 
the  smallest  quantity  of  water,  which  can  hold  it 
in  the  liquid  state,  it  is  called  concentrated  acid. 
TO  produce  this,  the  acid  itself  is  distilled  over, 
after  the  evaporation  of  the  water  is  finished,  Bui 


94  CLASS    III.      OXIDABLES. 

almost  any  experiment  may  be  performed  with  the  ' 
acid  which  is  prepared  by  slowly  evaporating  the 
water  from  it  in  an  open  plate. 

Remark.  Sulphuric  acid  is  the  key  to  most 
chemical  analyses.  It  is  made  by  a  direct  pro- 
cess. Whereas  nitric  acid  and  muriatic  acid,  be- 
ing the  other  two  powerful  acids,  are  obtained 
from  saltpetre  and  from  common  table  salt,  by  the 
agency  of  sulphuric  acid. 

Prop.  3.  Sulphur  may  be  combined  with  hydro- 
gen  and  form  the  bases  of  most  of  the  nauseous 
scents,  called  sulphuretted  hydrogen  gas. 

Illustration.  Mix  about  equal  bulks  of  finely 
pulverized  iron  filings  and  pulverized  sulphur. 
Put  this  mixture  into  a  crucible  ;  covering  it  over 
by  inverting  in  it  the  crm  ible  next  smaller  in  size, 
of  the  nest  of  crucibles  to  which  it  belongs.  Set  it 
upon  hot  coals  and  melt  the  mixture — lifttit  remain 
until  the  blue  blaze,  which  leaks  out  between  the 
crucibles,  ceases.  Now  empty  it  out,  which  will 
be  the  artificial  sulphuret  of  iron.  Next  proceed 
with  this  in  all  respects,  as  directed  for  obtaining 
hydrogen  gas,  with  this  addition;  that  after  the 
sulphuret  and  the  diluted  sulphuric  acid  are  mix- 
ed in  the  retort,  the  heat  of  the  caudle  must  be  ap 
plied  to  the  retort. 

This  gas  must  not  be  collected  in  the  cistern  ; 
but  the  receiver  must  be  filled  with  pure  clean 
rain  or  river  water  and  inverted  in  a  wash-bowl  or 
some  other  convenient  vessel,  so  that  no  metal- 
lic substance  shall  touch  the  water. 

Rationale.  The  iron  part  of  the  sulphuret  acts 
in  some  measure  as  it  does  in  the  production  of 
hydrogen  gas^  but  not  so  powerfully.  Therefore 


PRINCIPLE    3.       SULPHUR.  95 

the  aid  of  heat  is  required  to  strengthen  the  affini- 
ty. When  the  hydrogen  is  thus  disengaged  from 
the  oxygen  of  the  water,  sulphur  unites  with  it, 
and  a  compound  gas  is  produced. 

Application.  This  is  the  gas  which  is  generat- 
ed in  all  dirty  sinks,  and  other  places  ahounding 
in  such  filthy  substances.  It  is  so  destructive  to 
life,  that  a  horse  will  die  in  a  few  minutes  if  cov- 
ered with  a  cloth  and  exposed  to  it,  when  introduc- 
ed under  the  covering. 

Prop.  4.  Sulphuretted  hydrogen  gas  explodes 
on  being  inflamed  in  oxygen. 

Illustration.  Mix  it  with  oxygen  and  explode 
it  in  the  gas  pistol  in  all  respects  as  directed  with 
pure  hydrogen. 

Rationale.  Same  as  given  for  the  explosion  of 
hydrogen. 

Application.  There  may  possibly  be  a  suffi- 
cient quantity  of  this  gas  generated  about  the  kitch- 
ens and  sinks  of  filthy  housekeepers,  to  explode 
with  the  oxygen  of  the  atmosphere.  This  would 
be  a  dangerous  method  of  purification  "  by  fire." 
Earthquakes  are  supposed  to  be  caused  by  the  ex- 
plosion of  this  gas  in  most  cases  ;  because  the 
smell  is  perceived  wherever  an  opening  is  made 
by  the  explosion. 

Prop.  5.  Sulphuretted  hydrogen  gas  is  ab- 
sorbed rapidly  by  water;  and,  in  the  liquid  state, 
gives  a  dark  or  black  tinge  to  many  metals. 

Illustration.  White  the  gas  is  coming  over,  as 
before  mentioned,  let  some  pass  into  a  decanter, 
which  is  filled  with  rain  water  and  inverted,  until 
half  the  water  runs  out.  Put  the  thumb  over  the 
mouth  and  shake  the  decanter  violently.  It  will 


96  CLASS    III.       OXIDABLES. 

immediately  absorb  the  gas.  Now  pour  a  little 
into  a  wine  glass  and  drop  in  a  little  sugar  of  lead 
and  it  will  be  blackened.  Copperas,  blue  vitriol, 
white  vitriol,  and  other  metallic  salts  may  be 
dropped  into  different  glasses  of  the  liquid,  and  all 
will  receive  different  shades  of  colour.  A  piece 
of  silver  coin  will  also  become  brown  if  immersed 
in  it  a  while,  especially  in  the  roughest  parts  of  it. 
Rationale.  There  is  some  difficulty  in  giving 
a  satisfactory  reason  for  these  various  appearan- 
ces of  metallic  oxids.  As  a  portion  of  the  gas  is 
always  decomposed  during  the  process,  it  is  pro- 
bable that  a  sulphuret,  more  or  less  perfect,  is 
formed  with  the  metal. 

Application.  When  lead  is  suspended  in  wa- 
ter, this  liquid  is  a  ready  test.  Silver  spoons,  &c. 
often  exhibit  dark  coloured  spots,  which  appear 
unaccountable  to  housekeepers.  These  are  ge- 
nerally caused  by  liquid  sulphuretted  hydrogen, 
generated  about  filthy  sinks,  &c.  Ladies  who  paint 
their  faces  with  a  cosmetic,  whose  base  is  bismuth 
or  other  metal,  often  become  tawny  by  approach- 
ing an  old  dock  or  sewer. 

Many  natural  springs  are  highly  charged  with 
sulphuretted  hydrogen.  They  are  always  useful 
in  cutaneous  eruptions ;  and  are  generally  called 
Harrowgate  springs,  from  their  resembling  the 
Harrowgate  waters  in  England.  They  are  dis- 
tinguished by  the  smell  of  sulphur,  or  by  testing 
with  sugar  of  lead. 

PHOSPHORUS. 

Natural  History  and  general  Remarks. 
Phosphorus;  the  most  combustible  of  all  simple 


PRINCIPLE   4.      PHOSPHOHUS.  97 

solids,  is  always  found  in  nature  in  the  state  of 
an  acid  ;  mostly  forming  a  salt  with  lime.  Bones 
of  animals  consist  chiefly  of  phosphoric  acid  and 
lime. 

Bat  phosphorus  is  not  a  recently  created  sub- 
stance. In  truth,  it  seems  that  all  material  sub- 
stances were  created  at  the  same  time.  For  we 
find  those  which  appear  to  us  the  most  recent, 
fugitive,  changeable  and  transitive,  in  connec- 
tion with  those  which  we  are  disposed  to  consider 
the  oldest  and  most  permanent.  Phosphate  of 
lime,  a  compound  similar  to  animal  bones,  is  found 
in  the  oldest  granite  ;  though  rarely  in  transition 
or  secondary  rocks. 

The  process  for  obtaining  phosphorus  is  too  la- 
borious and  difficult,  to  be  performed  in  the  course 
proposed  in  this  work.  It  is  obtained  from  ani 
inal  bones.  The  lime  is  easily  disposed  of  by 
soaking  the  bones  in  diluted  sulphuric  acid,  after 
they  have  been  burned  to  whiteness  and  pulveriz- 
ed. But  to  separate  the  oxygen  from  the  phos- 
phorus, after  the  phosphoric  acid  is  freed  from 
the  lime,  requires  a  high  and  long  continued  heat ; 
and  it  requires  considerable  experience  to  con 
duct  this  part  of  the  process  with  success.  It  may 
be  purchased  at  a  dollar  and  a  half  or  two  dollars 
per  ounce.  Half  an  ounce  will  be  sufficient  for  a 
course  of  instruction. 

Prop.  i.     Phosphor  us  decomposes  water,  slow 
ly  when  the  water  is  in  the  liquid  state9  but  with 
considerable  rapidity  when  in  the  vaporous  state. 

Illustration.  Expose  a  stick  of  phosphorus  to 
water  several  days  in  a  vial,  and  the  outside  will 
be  covered  with  a  white  substance,  which  is  the 
oxid  of  phosphorus.  The  oxid  is  more  inflamma- 

9 


98  CLASS    III.       OXIDABLES. 

ble  than  pure  phosphorus.  ,  If  a  little  be  scraped 
off  and  exposed  to  the  rays  of  the  sun,  in  a  short 
time  it  will  take  fire. 

Put  water  into  a  small  vial  or  test  glass  (pre- 
viously filled  with  nitrogen  gas)  just  sufficient  to 
cover  the  bottom  Then  put  in  a  stick  of  phospho- 
rus, and  cork  it  perfectly  tight.  Set  it  in  a  warm 
room  a  few  days,  and  the  outside  of  the  stick  of 
phosphorus  will  be  covered  with  phosphoric  acid. 

Rationale.  In  the  first  case  the  strength  of  affi- 
nity but  feebly  decomposes  the  water  in  the  liquid 
state.  In  the  last  case  the  small  quantity  of  wa- 
ter passing  into  a  state  of  vapour  is  more  easily  de- 
composed. 

Application.  Sticks  of  phosphorus  kept  in 
vials  of  water  in  the  common  way,  are  always 
covered  on  the  outside  with  the  oxid.  I  once  set 
a  gallipot  in  a  desk  in  Rutland  court-house,  Ver- 
mont, to  the  inside  of  which  a  little  oxid  of  phos- 
phorus adhered.  The  weather  was  extremely 
cold,  and  it  stood  undisturbed  and  forgotten  for 
several  days.  At  length  a  crowded  assembly  oc- 
cupying the  room  one  evening,  and  the  tempera- 
ture of  the  air  being  considerably  raised,  it  took 
fire  spontaneously  and  burned  rapidly.  If  a  vial 
be  heated  a  little,  and  a  piece  of  phosphorus  at- 
tached to  the  end  of  a  wire  be  rubbed  about  the 
inside  of  the  vial,  in  a  half  melted  state,  so  as  to 
coat  it,  this  will  be  the  phosphoric  match  vial. 
This  being  the  oxid  of  phosphorus,  if  a  little  be 
taken  out  and  exposed  to  the  air,  if  the  weather 
is  not  very  cold,  it  will  take  fire  spontaneously. 
The  vial  must  be  kept  corked — and  even  when  it 
is  preparing,  it  may  take  fire  and  require  the  vial 
to  be  stopped  a  moment  until  it  is  extinguished. 


PRINCIPLE    4.       PHOSPHORUS.  99 

Prop.  2.  By  light  friction  phosphorus  becomes 
oxidated,  and  during  the  process  a  partial  com- 
bustion and  illumination  takes  place. 

Illustration.  Rub  a  stick  of  phosphorus  light- 
ly on  a  board.  The  phosphorus  which  is  left  on 
the  board  will  be  luminous  in  the  dark,  arid  by 
blowing  upon  it,  undulating  waves  of  light  will 
appear  and  vanish. 

Rationale.  Though  the  phosphorus  does  not 
break  out  into  a  flame,  oxygen  unites  with  it  with 
such  force  as  to  disengage  sensible  heat  and  light^ 
and  to  produce  an  acid  or  oxid.  All  combustion 
is  caused  by  the  combination  of  oxygen  with  the 
combustible  substance,  and  all  oxidations  would 
produce  combustion,  did  not  the  process  go  on  too 
slow  to  render  the  disengagement  of  caloric  mani- 
fest to  the  senses.  In  this  case,  the  light  is  mani- 
fest in  the  dark. 

Application.  Letters  or  even  sentences  may  be 
written  on  board  ceilings,  &c.  which  may  be  read 
in  the  dark  for  fifteen  or  twenty  minutes.  During 
their  illumination,  the  phosphorus  is  manifestly 
in  a  state  of  imperfect  combustion,  and  becomes 
oxidated. 

Prop.  3.  Phosphorus  on  being  inflamed  in  at- 
mospheric air,  will  unite  with  its  highest  definite 
proportion  of  oxygen  and  form  phosphoric  acid. 

Illustration.  Set  oil  the  table  a  perfectly  dry 
earthen  plate.  Lay  upon  the  centre  of  it  a  piece 
of  a  stick  of  phosphorus  one  third  of  an  inch  iu 
length.  Set  it  on  fire  and  invert  over  it  a  perfect- 
ly dry  half-gallon  tubulated  bell-glass.  Raise 
one  edge  of  the  bell-glass  half  an  inch  by  inclin- 
ing it  a  little  towards  one  side,  or  placing  a  chip 
under  it.  Start  the  stopper  of  the  tubulature  a 


100  CLASS    III.      OXIDABLES. 

little,  so  as  to  permit  the  nitrogen  gas  to  escape, 
as  the  oxygen  of  the  air  in  the  hell-glass  becomes 
exhausted.  In  this  way  continue  the  combustion 
of  the  phosphorus  until  it  is  nearly  consumed. 
The  inside  of  the  bell-glass  will  exhibit  the  ap- 
pearance of  a  snow-storm,  and  a  considerable 
depth  of  dry  white  phosphoric  acid  will  fall  upon 
the  plate.  This  acid  strongly  attracts  water,  like 
the  other  acids  It  will  become  liquid,  though 
corked  up  in  a  vial,  unless  much  care  is  taken  to 
make  the  vial  perfectly  dry,  and  to  fit  in  the  cork 
very  tight  when  it  is  dry. 

While  the  acid  remains  untouched  and  dry  on 
the  plate,  dip  a  fine  shaving  brush  into  cold  wa- 
ter arid  strike  it  across  the  finger,  so  as  to  sprinkle 
very  fine  drops  of  water  upon  the  dry  acid,  and 
minute  brilliant  sparks  will  appear.  I  have  not 
seen  any  notice  of  this  fact  published.  It  may 
have  been  published  ;  but  it  was,  so  far  as  respects 
my  knowledge  of  the  subject,  an  original  discove- 
ry made  by  one  of  the  students  of  the  Rensselaer 
School.  I  am  not  prepared  to  assign  a  reason  for 
this  appearance. 

Rationale.       Same  as  that  frequently  given  al 
ready,  in  regard  to  the  union  of  acidifyabies  with 
oxygen. 

Application.  This  acid  is  not  much  used.  It 
is  ready  formed  in  animal  bones,  as  before  observ- 
ed. It  is  used  in  medicine  in  combination  with 
soda  and  some  other  bases. 

Prop.  4.  Phosphorus  may  be  inflamed  under 
water  by  furnishing  it  with  a  due  portion  of  oxy- 
gen. 

Illustration.  Put  a  piece  of  phosphorus  into  a 
tall  narrow  cylindric  glass  which  is  filled  with 


PRINCIPLE   1.      PHOSPHORUS.  101 

cold  water,  and  put  in  with  it  about  three  times  as 
much  oxymuriate  of  potash.  Bring  the  two  sub- 
stances in  contact  with  each  other.  Provide  a 
very  long  tube  and  stop  up  the  lower  end  and  fill 
it  with  sulphuric  acid,  before  it  is  put  into  the  wa- 
ter. Then  press  the  thumb  upon  the  upper  end 
of  the  tube  and  unstop  the  lower  end,  at  the  in- 
stant it  is  to  be  put  in.  After  the  open  end  of  the 
tube  is  brought  in  contact  with  the  salt,  the  thumb 
may  be  raised  up  and  pressed  down,  so  as  to  fur- 
nish the  quantity  of  acid  required  to  continue  the 
flame. 

The  phosphorus  may  be  inflamed  also  by  forc- 
ing a  stream  of  oxygen  upon  the  phosphorus, 
through  a  tube  from  a  bladder.  But  in  this  case 
the  water  must  be  hot,  nearly  at  boiling  heat. 

Rationale.  Such  is  the  strength  of  attraction 
between  phosphorus  and  oxygen,  that  they  will 
unite  and  produce  combustion  even  when  invel- 
oped  in  water,  whether  immediately  presented  or 
obtained  from  a  salt. 

Application.  This  experiment  has  its  use  in 
familiarizing  our  minds  with  the  correct  princi- 
ples of  combustion. 

Prop.  5.  Phosphorus  may  he  made  to  unite 
with  hydrogen,  forming  a  compound  which  ex- 
plodes and  burns  spontaneously  in  atmospheric 
air,  called  phosphuretted  hydrogen  gas, 

Illustration.  Procure  a  tin  vessel,  called  a 
jack-o?lantern  basin,  made  as  follows.  Have  an 
inch  hole  made  through  the  bottom  of  a  tin  quart 
basin.  Have  a  tin  quart  decanter  made  with  strait 
sides.  Let  the  mouth  of  the  decanter  be  soldered 
to  the  under  side  of  the  basin,  so  as  to  fit  the  hole 


102  CLASS    III.      OXIDABLES, 

in  the  basin.  Now  introduce,  through  the  hole  in 
the  bottom  of  the  quart  basin,  into  the  decanter 
part,  a  mixture  of  two  parts  of  dry  newly  slacked 
lime  and  one  of  dry  pearlash,  pouring  in  occasion- 
ally a  little  cold  water,  just  sufficient  for  a  thick 
paste,  until  it  is  almost  filled  to  the  bottom  of  the 
basin  part.  Drop  in  about  two  inches  of  a  stick 
of  phosphorus.  Stir  the  whole  well,  so  as  to  mix 
all  parts  thoroughly. 

Set  the  decanter  part  upon  coals,  or  suspend  it 
over  a  lamp.  Let  the  beat  be  raised  moderately. 
Before  the  mass  is  to  a  boiling  heat,  bubbles  of 
the  gas  will  appear  in  the  neck  and  explode. 

Now  fill  the  neck  with  water,  and  lay  upon  the 
mouth  a  piece  of  lead  about  two  inches  in  diame- 
ter with  a  hole  in  the  center  about  the  size  of  a 
pipe- stem.  Fill  up  the  basin  with  water,  which 
must  be  occasionally  changed  by  dipping  out. 
when  it  becomes  too  warm.  Bubbles  of  gas  will 
rise  to  the  top  of  the  water,  explode  and  form  an 
ascending  comma  or  wreath  ;  but  they  may  some- 
times spread  over  the  surface  of  a  very  small  size, 
Break  off  the  foot  of  a  wine-glass  and  use  it  for  a 
receiver,  for  collecting  and  turning  up  large  bub- 
bles, and  for  transferring  gases  into  a  cistern. 

Rationale.  Phosphorus  decomposes  water,  and 
unites  with  the  hydrogen  of  the  water  in  its  eva- 
nescent state.  But  it  seems  to  require  the  pres- 
ence of  an  alkali  to  create  in  it,  in  some  unexplain- 
ed manner,  a  pre-disposition  to  decompose  the 
water.  See  Carbon,  Prop. .  7. 

Application.  This  is  an  exhibition  of  the jack- 
o'lantern,  so  often  seen  about  places  where  ani- 
mal bodies  are  putrifying  in  damp  ground.  But 
nature  has  a  method  of  combining  the  phosphuret- 


PRINCIPLE  4.      PHOSPHORUS.  IOB 

ted  hydrogen  with  something,   which  causes  it  to 
burn  more  steadily  and  to  endure  longer. 

Prop.  6.  Phosphuretted  hydrogen  gas  ex- 
plodes spontaneously,  and  with  great  brilliancy 
in  oxygen  gas. 

Illustration.  "While  the  bubbles  of  phosphuret* 
ted  hydrogen  gas  are  ascending,  pass  a  wine-glass 
of  it  under  a  hole  in  the  shelf,  over  which  is  set  a 
strong  bell-glass,  with  about  a  half  pint  of  oxygen 
in  the  upper  part  of  it.  After  a  bubble  has  as- 
cended through  the  water  of  the  bell-glass  and 
comes  in  contact  with  the  oxygen,  it  will  explode 
with  a  brilliant  illumination.  JSut  if  any  bubbles 
pass  into  the  oxygen  and  break  without  explod- 
ing, they  will  mix  with  the  oxygen  and  form  an 
explosive  compound.  Then  if  succeeding  bub- 
bles should  explode,  the  whole  would  explode 
and  break  the  bell-glass  with  some  danger  to  the 
auditors.  Therefore,  if  this  happens,  the  process 
must  be  discontinued,  and  the  oxygen  removed. 
See  Silliman's  Journal. 

Rationale.  It  seems  that  the  combustible  qual- 
ities of  these  two  very  combustible  substances, 
are  strengthened  by  their  union.  Though  each 
attracts  oxygen  powerfully  while  separate,  when 
combined  they  even  attract  it  from  the  atmosphere 
with  sufficient  force  to  explode  spontaneously. 

Application.  This  experiment  ought  to  satisfy 
our  minds,  that  the  pretended  mysteries  of  conju- 
rors and  showmen  are  but  the  application  of  their 
smattering  knowledge  of  a  few  scientific  facts. 

Prop.  7.  Phosphorus  dissolves  in  warm  oil, 
and  in  that  state  is  luminous  in  the  dark  when  ex- 
posed  'to  atmospheric  air. 


104  CLASS    III.      OXIDABLES. 

Illustration.  Fill  an  ounce  vial  two  thirds  full 
of  sweet  oil.  Put  some  shavings  of  phosphorus 
into  it ;  ahout  half  an  inch  of  a  common  stick  will 
be  sufficient.  Hold  the  vial  near  the  fire,  until  it 
is  ahout  as  hot  as  can  be  borne  by  the  hand,  and 
keep  it  at  this  temperature  until  the  phosphorus  is 
melted.  Now  if  the  cork  is  taken  but,  the  upper 
part  of  the  vial  will  become  luminous  in  the  dark 
by  the  admission  of  air.  Cover  all  the  lights  in 
the  room,  pour  two  or  three  tea- spoonfuls  of  it 
into  the  hand,  and  rub  it  thoroughly  over  a  boy's 
face  and  hair,  and  let  him  show  himself  to  the 
class.  His  face  will  be  singularly  luminous,  and 
his  hair  will  exhibit  a  kind  of  undulating  flame, 
It  must  not  be  forgotten  in  this  experiment,  that 
the  vial  is  to  be  warm,  but  not  hot,  so  that  the  oil 
may  be  of  a  temperature  about  equal  to  blood  heat 
whenever  it  is  to  be  applied,  and  there  must  be  no 
unmelted  piece  of  phosphorus. 

Rationale.  Caloric  and  light  generally  accom- 
pany each  other.  Consequently  combustion  pro- 
duces light.  In  this  case  there  is  manifestly  a 
partial  combustion.  This  appears  from  the  fact, 
that  when  air  is  admitted  by  unstopping  the  vial, 
it  becomes  luminous  ;  but  on  stopping  it  again  it 
becomes  dark  as  soon  as  the  oxygen  of  the  admit- 
ted air  is  expended. 

Application.  Although  many  luminous  mete- 
ors traverse  the  atmosphere,  called  shooting  stars, 
&c.  which  have  never  been  subjected  to  analysis  ; 
yet  these  three  last  experiments  go  far  towards 
a  solution  of  such  phenomena. 

PRINCIPLE    5.       CARBON, 

Natural  History  and  general  Remarks. 
Carbon  is  pure  in  the  state  of  a  diamond  only. 


PRINCIPLE    5.       CARBON.  105 

Common  charcoal  is  always  combined  with  a  lit- 
tle oxygen.  Carbon  is  abundant  in  nature  in  va- 
rious states.  In  the  pitcoal  if  exists  in  combina- 
tion with  a  little  oxygen,  bitumen,  sulphur,  &c. 
In  the  anthracite  or  glance  coal  it  is  more  pure 
than  in  any  other  state,  excepting  the  diamond. 
Combined  with  oxygen  in  the  state  of  gas,  it  floats 
in  the  atmosphere.  It  forms  a  constituent  part 
of  marble,  of  chalk,  of  all  vegetable  and  animal 
matter,  &c. 

Carbonate  of  lime  is  found  disseminated  in  gra- 
nite ;  therefore  carbon  is  associated  with  the  old- 
est rocks  in  the  solid  state,  while  we  give  off  por- 
tions of  it  from  our  lungs  in  the  state  of  gas  at 
every  respiration. 

Prop.  l.     Charcoal,  when  cold,  absorbs  sul 
phuretted  hydrogen  gas,  ammoniacal  gas,  carbu* 
retted  hydrogen  gas,  carbonic  acid  gas,  £fc.  and 
gives  them  off  again  when  heated. 

Illustration.  Prepare  these  gases  according  to 
the  directions  heretofore  given,  and  hereafter  to 
be  given  :  fill  small  glass  cylinders  or  opodeldoc 
vials  with  them  separately,  and  place  them  over 
mercury.  Cut  pieces  of  charcoal  of  a  size  which 
will  easily  enter  the  mouths  of  the  glass  cylinders. 
Take  the  pieces  separately  into  the  small  crooked 
wire  tongs  and  hold  them  over  a  hot  fire,  until 
they  become  red  hot.  Take  them  from  the  fire 
and  scrape  off  the  outside  a  little,  and  plunge  them 
into  mercury  to  cool  without  coming  in  contact 
•with  the  air.  After  they  are  perfectly  cooled, 
pass  them  separately  into  the  several  cylinders  of 
gas,  still  holding  them  in  the  tongs,  and  a  con- 
siderable quantity  of  each  will  be  absorbed,  and 
the  mercury  will  ascend  to  fill  the  vacuum.  After 


106  CLASS    III.      OXIDABLES. 

these  pieces  of  coal  are  saturated,  draw  them  out 
through  mercury  (at  least  one  or  two  of  them)  and 
heat  them  again.  On  applying  them  a  second 
time,  it  will  be  found  that  the  heat  has  driven  out 
the  gases,  as  they  will  again  absorb  them  as  be- 
fore. 

A  little  mercury  will  be  found  pressed  into  the 
pores  of  the  coal ;  but  this  does  not  affect  the  ex- 
periment, as  the  coal  will  absorb  the  gases  equal- 
ly well,  though  a  little  slower. 

Rationale.  The  absorbing  property  of  char- 
coal commences  from  the  moment  of  its  manufac- 
ture at  the  coalpit — consequently  it  absorbs  the 
first  of  these  gases  with  which  it  comes  in  contact 
after  cooling.  By  heating,  the  absorbed  gas  is 
disengaged  ;  then  on  cooling,  it  again  absorbs  as 
above  shown. 

Application.  There  is  not  an  experiment 
known  in  chemistry,  which  explains  more  of  the 
practical  principles  of  agriculture  and  domestic 
economy,  than  this.  All  the  gases  which  are  pro- 
duced when  animal  matter  passes  into  a  state  of 
putrefaction  being  absorbed  by  it,  it  is  very  im- 
portant in  resisting  and  checking  the  progress  of 
putrefaction.  A  tooth-powder,  made  by  heating 
finely  pulverized  charcoal  to  redness  in  an  iron 
skillet,  and  pouring  it  while  hot  into  a  bowl  of 
clean  water,  is  the  best  of  all  known  substances 
to  preserve  the  teeth  from  decay,  or  to  prevent 
further  decay  after  it  had  commenced.  For  the 
gases  being  all  driven  out  by  heat,  the  charcoal 
absorbs  water  and  sinks  in  it.  If  kept  in  a  bottle, 
it  will  remain  under  water,  defended  from  the  gas- 
es, and  if  shaken  up  and  a  tea-spoonfull  be  taken 
occasionally  into  the  mouth,  and  the  teeth  rubbed 
with  itj  every  thing  impure  will  be  absorbed. 


PRINCIPLE  5.       CARBON.  107 

Putrid  meat  will  become  purified  by  immersing 
it  in  a  similar  preparation.  Putrid  water  is  also 
purified  by  pouring  into  it  heated  'charcoal  pow- 
der, &<•.  &c. 

Carbonaceous  manures,  as  rotted  straw,  leaves, 
&c.  furnish  food  for  vegetables  upon  the  same 
principle.  In  the  cool  season  of  night  they  ab- 
sorb carbonic  acid,  carbu retted  hydrogen,  ammo- 
nia, &c.  which  they  give  off  under  the  heating 
?ays  of  the  sun,  during  the  day,  to  the  absorbent 
vessels  of  the  fibrous  roots  of  plants. 

Prop.  2.  Charcoal,  if  exposed  to  oxygen  gas 
in  a  state  of  ignition,  will  combine  with  it?  and 
form  carbonic  acid  gas. 

Illustration.  Fill  a  glass  cylinder  or  opodel- 
doc vial,  with  oxygen  gas  in  the  cistern,  slip  across 
its  mouth  a  piece  of  paste-board,  turn  it  up  and 
set  it  near  the  mercurial  trough.  Expose  a  small 
piece  of  charcoal  to  a  strong  heat,  holding  it  in 
the  tongs  until  it  is  red  hot  and  burning.  Sow 
lay  it  upon  the  surface  of  the  mercury,  and  hold- 
ing the  paste-board  pressed  upon  the  tumbler, 
bring  it,  with  the  top  downwards,  over  the  burn- 
ing charcoal.  Quickly  remove  the  paste  board, 
and  shut  the  tumbler  closely  over  the  coal.  It  will 
burn,  throwing  off  bright  sparks,  until  so  much  of 
it  has  become  a  gas  and  combined  with  the  oxy- 

fm,  as  to  convert  the  whole  into  carbonic  acid, 
be  bulk  of  the  gas  will  neither  increase  nor  di- 
minish, but   become   specifically  heavier.      The 
oxygen  must  be  perfectly  pure. 

Now  draw  out  the  coal  through  the  mercury, 
slip  the  paste-board  across  the  mouth  of  the  tum- 
bler, turn  it  up  and  set  it  on  the  table.  Immerse 
a  burning  candle  in  it,  and  it  will  be  extinguished. 


108  CLASS    III.      OXIDABLES* 

Test  it  also  with  limpid  lime  water.  This  may  be 
performed  most  conveniently,  by  carefully  letting; 
down  into  it  a  low  glass  cup  of  lime  water.  It 
will  soon  be  covered  with  a  white  or  grey  pellicle. 
A  very  small  watch  glass  will  do,  if  it  is  not  con- 
venient to  obtain  any  other. 

'Rationale.  Carbon  has  a  strong  affinity  for 
oxygen,  but  will  not  combine  with  it,  while  in  a 
solid  state  unless  its  affinity  is  strengthened  by  the 
aid  of  caloric.  As  soon  as  the  combination  takes 
place,  such  is  the  nature  of  this  compound,  that  it 
assumes  the  gaseous  form  and  remains  a  perma- 
nent gas  iti  every  known  temperature. 

Application.  A  kettle  of  burning  coals  is  fre- 
quently set  into  a  close  bed-room  on  a  cold  night. 
Carbonic  acid  gas  is  formed  by  the  union  of  the 
charcoal  with  the  oxygen  of  the  ataiosphere,which 
frequently  destroys  life. 

Prop.  3.  Carbonic  acid  exists  in  combination 
with  lime,  forming  chalk,  common  limestone,  or 
marble,  from  which  it  may  be  obtained  by  elective 
affinity. 

Illustration.  Pulverize  a  fragment  of  marble, 
and  put  a  wine  glass  full  into  a  pint  retort.  Pour 
on  it  about  a  gill  of  water.  After  it  has  soaked 
about  a  minute,  pour  in  slowly  half  a  wine  glass 
of  sulphuric  acid,  diluted  with  about  five  times  as 
much  water.  The  carbonic  acid  will  come  over 
in  a  state  of  gas,  and  may  be  collected  in  any  re- 
ceiver placed  on  a  shelf  of  the  cistern. 

Rationale,  Lime,  which  constitutes  the  basis 
of  the  marble,  elects  the  sulphuric  acid,  and  there- 
by excludes  the  carbonic  acid.  The  latter  acid, 
as  soon  as  it  is  eliminated  from  its  connexion  with 
the  lime,  absorbs  caloric  from  the  atmosphere  and 


PRINCIPLE   5.      CARBOK.  i09 

other  surrounding  bodies  in  sufficient  quantities  to 
convert  it  into  a  gas,  from  the  solid  state  in  which 
it  existed  while  it  constituted  an  essential  part  of 
the  raarhle. 

Application.  On  this  principle  the  carbonic 
acid  for  making  acidulous  water,  improperly  call- 
ed soda  water,  is  obtained.  But  by  what  process 
nature  disengages  the  vast  quantity  of  this  gas. 
which  is  required  to  charge  the  Saratoga  and 
Ballston  waters  so  highly,  no  one  has  hitherto 
suggested  even  a  plausible  conjecture. 

Prop.  4.  Carbonic  acid  gas  is  absorbed  by  wa- 
tery and  in  that  state  of  combination  gives  the  acid 
test. 

Illustration.  Pass  some  of  the  gas  into  a  de 
canter  of  pure  cold  water  and  agitato  it,  until  the 
water  and  gas  are  well  mixed.  Pour  into  a  wine- 
glass of  it  some  of  the  blue  infusion  of  red  cabbage, 
and  it  will  become  of  a  very  light  red  colour.  The 
infusion  ought  rather  to  be  greenish  when  put  in, 
by  putting  into  it  an  extremely  small  quantity  of 
an  alkali  before  it  is  used,  otherwise  the  change 
in  colour  made  by  the  acidulous  water  will  hardly 
be  perceived. 

Rationale.  This  is  one  of  those  primary  facts, 
for  which  no  satisfactory  rationale  can  be  given. 
We  can  say  little  more  in  such  cases,  than  that  so 
is  the  fact. 

Application.  This  proves  the  fixed  air  to  be 
an  acid  gas.  The  taste  of  the  water  also  indicates 
its  acid  quality.  Carbonated  waters,  called  soda 
waters,  are  prepared  upon  this  principle.  The 
quantity  of  carbonic  acid  gas,  absorbed  by  the 
water,  depends  on  the  coldness  of  the  water,  and 

10 


110  CLASS    III.      OXIDABLES* 

the  force  applied  to  compress  the  gas,  while  in? 
contact  with  the  water.  The  waters  sold  under  the 
name  of  soda  waters,  as  prepared  in  most  of  our 
towns,  contain  both  sulphurous  acid  and  muriatic 
acid.  Chalk  is  commonly  used,  which  generally 
contains  a  little  muriate  of  soda.  This  being  de- 
composed furnishes  muriatic  acid  ;  and  it  is  im- 
possible to  avoid  a  little  mixture  of  sulphurous 
acid,  arising,  probably,  from  a  slight  decomposi- 
tion of  some  portion  of  the  sulphuric  acid,  used 
in  the  process.  To  cleanse  the  gas  from  these 
deleterious  impurities,  Mr  Meigs,  of  Albany, 
prepares  this  gas  and  forces  it  once  through  his 
condenser,  containing  a  small  quantity  of  water, 
before  he  introduces  the  water  for  use.  The 
small  quantity  of  water  readily  absorbs  all  the 
muriatic  acid  and  sulphurous  acid,  and  wastes  a 
little  carbonic  acid.  This  being  drawn  off  and 
pure  water  added,  the  carbonated  water  is  made 
very  pure. 

Prop.  5.  Carbonic  acid  gas  is  heavier  than 
atmospheric  air,  extinguishes  flame,  and  des- 
troys life  when  breathed. 

Illustration.  Immerse  a  candle,  suspended  by 
a  wire,  in  a  tumbler  containing  atmospheric  air, 
and  let  it  be  observed  that  it  burns  as  it  did  in  air 
not  contained  in  the  tumbler.  Take  out  the  can- 
dle and  invert  a  glass  cylinder  or  opodeldoc  vial, 
which  is  filled  with  carbonic  acid  gas,  in  the  tum- 
bler. The  cylinder  should  be  smaller  than  the 
tumbler,  so  that  its  mouth  may  enter  the  mouth  of 
the  tumbler;  and  the  mouth  of  the  cylinder  must 
be  covered  with  wet  paste-board,  until  it  is  brought 
directly  over  the  tumbler  After  holding  the  glass 
cylinder  in  this  position  about  eight  or  ten  seconds,, 


PRINCIPLE    5.       CARBON.  Ill 

the  gas  will  have  settled  down  into  the  tumbler. 
Now  immerse  the  candle  again,  and  it  will  he  ex- 
tinguished. The  gas  will  remain  in  the  tumbler, 
and  still  extinguish  a  candle  for  any  length  of  time 
if  a  piece  of  dry  paste- board  be  loosely  laid  over 
it,  so  as  to  prevent  its  being  driven  out  by  the  mo- 
tion of  the  air. 

Fill  a  glass  cylinder  with  carbonic  acid  gas,  set 
it  on  the  table  with  the  mouth  upwards,  and  put  a 
live  mouse  into  it.  The  mouse  will  appear  con- 
vulsed for  a  moment  and  expire. 

Rationale.  Gases,  as  well  as  liquids  and  sol- 
ids, of  the  greatest  specific  gravity,  tend  to  occupy 
the  lowest  position.  As  gases  move  freely  among 
each  other,  the  heaviest  descends  of  course,  unless 
assisted  by  the  attraction  of  affinity  or  of  adhesion. 
In  this  experiment,  it  is  probable  that  some  of  the 
carbonic  acid  gas  co  nbines  with  atmospheric  air: 
but  after  the  latter  is  fully  saturated,  the  former 
settles  at  the  bottom  of  the  tumbler  nearly  pure. 
Its  properties  are  then  rendered  manifest  by  ex- 
tinguishing the  candle,  &c. 

Application.  This  is  the  gas  usually  called 
choak  damps,  by  miners.  Being  heavier  than  at- 
mospheric air,  it  settles  down  into  wells  and  cav- 
erns, and  often  destroys  the  lives  of  miners.  As 
it  is  absorbed  by  water,  unless  it  is  very  rapidly 
produced,  none  will  be  found  to  remain  in  wells 
which  contain  water;  but  it  is  generally  found  in 
deep  dry  wells,  which  are  dug  in  very  compact 
earth  or  in  rocks.  In  all  such  cases,  a  candle 
should  be  let  down  before  the  well  is  entered. 
But  the  gas  ma,y  be  found  in  wells  containing  wa- 
ter ;  for  water  will  not  generally  absorb  more 
than  Us  bulk  of  the  gas  in  twenty-four  hours,  and 


112  CLASS    III.     -OXIDAELES. 

a  larger  quantity  may  be  accumulated  in  that  time* 
especially  in  limestone  countries. 

Prop.  6.  Carbonic  acid  gas  may  always  be 
found,  in  a  greater  or  less  proportion,  suspended 
''"w  the  atmosphere. 

Illustration.  Pour  a  tea-spoon  of  limpid  lime 
water  into  a  clean  decanter.  Shake  it  smartly, 
and  the  lime  water  will  become  milky. 

Rationale.  The  milky  appearance  of  the  lime 
water  demonstrates  the  presence  of  carbonic  acid. 
As  the  decanter  contained  common  atmospheric 
air,  the  presence  of  carbonic  acid  in  combination 
is  proved. 

Application.  Carbonic  acid  is  found  to  be  ex- 
cellent food  for  plants,  when  absorbed  by  fresh 
earth,  by  carbonaceous  manure,  &c.  as  before  ob- 
served. Therefore  its  suspension  in  the  atmos- 
phere affords  an  inexhaustible  fund  of  vegetable 
nutriment. 

Prop.  7.  Carbonic  acid  gas  is  given  out  bij 
animals  at  every  respiration,, 

Illustration.  Put  some  limpid  lime  water  into 
a  wine  glass  and  breathe  in  it  through  a  tube  ex- 
tend i tig  to  the  bottom  of  the  glass.  After  thus 
exciting  a  bubbling  in  the  lime  water  five  or  six 
seconds,  it  will  become  milky. 

Rationale.  As  the  milky  appearance  of  lime 
water  has  never  been  produced  by  any  limpid  gas 
excepting  the  carbonic  acid,  it  is  evident  that  this 
gas  is  contained  in  the  breath.  That  its  propor- 
tion in  the  breath Js  much  greater  than  in  the  in- 
haled atmospheric  air,  may  be  shown  by  compar- 
ing the  different  effects  produced  by  blowing  the 
breath  into  one  glass  of  lime  water,  and  blowing 


PRINCIPLE   5.      CABBON, 

common  air  into  another  from  a  clean  tube  fitted 
to  the  pipe  of  a  hand  bellows. 

Application.  It  was  observed  under  oxygen, 
that  the  pure  oxygen  was  given  off  from  vegeta- 
bles by  the  action  of  light;  which  oxygen  is  es- 
sential to  the  health  and  even  to  the  existence  of 
animals.  Here  we  perceive,  by  this  experiment, 
that  animals  inreturn  ^ive  off  carbonic  acid,  which 
is  most  important  to  the  growth  of  vegetables. 
Therefore  animals  and  vegetables  ought  to  live 
near  each  other. 

Prop.  8.  Carbon  and  hydrogen  may  be  united, 
forming  the  light  carburetted  hydrogen  gas,  by  de- 
composing water  with  charcoal.  This  is  called 
the  blue  gas  9  from  the  colour  of  its  flame, 

Illustration.  Collect  some  pieces  of  charcoal 
from  an  old  coalpit  bed,  or  from  some  other  place, 
where  the  coal  has  been  exposed  to  the  weather 
several  years,  and  become  intimately  combined 
with  water.  Dry  it,  pulverize  it,  and  heat  it  in  a 
gun-barrel,  as  directed  in  procuring  oxygen  from 
manganese.  The  'beat  must  be  raised  suddenly  5 
for  a  slow  heat  will  evaporate  the  water  with  but 
very  little  combination.  Collect  it  in  the  cistern, 
and  put  some  into  a  gas-holder  and  burn  it  as  di=- 
lected  in  burning  hydrogen.  It  will  burn  with  9. 
blue  flame,  without  giving  much  light. 

Rationale.  Water  being  intimately  mixed  witfe 
the  charcoal  and  held  in  union  with  it  by  the  at- 
traction of  adhesion,  by  the  application  of  heat 
the  oxygen  of  the  water  unites  with  a  portion  of 
the  carbon.  The  water  being  thus  decomposed, 
its  hydrogen  unites  with  another  portion  of  carbon* 
forming  the  compound  gas. 

10* 


114  CLASS    III.      OXIDABLE9* 

Application.  As  in  this  case  the  charcoal  de 
composes  the  water  which  it  held  in  combination, 
and  a  part  of  it  unites  to  the  hydrogen  ;  so  decay- 
ing or  putrifying  vegetables  in  swamps,  &c.  de- 
compose water  and  form  the  same  gas,  which  is 
generally  called  marsh  miasmata.  It  appears  too 
in  the  bottom  of  stagnant  ponds,  &c.  which  may 
be  collected  in  bubbles  by  pressing  upon  the  mul- 
chy  sediment. 

Prop.  9.  Carburetted  hydrogen  gas  will  ex- 
plode when  inflamed  with  oxygen. 

Illustration.  Mix  the  gases  in  equal  volumes 
in  a  bell-glass  or  tumbler.  Pour  this  into  a  nar- 
row mouthed  bottle  or  decanter.  Sink  the  bottle 
under  the  water  of  the  cistern,  holding  the  thumb 
over  the  mouth.  Having  wet  a  roll  of  paper  iti 
spirits  of  turpentine,  light  it  and  hold  it  close  to 
the  water  over  the  bottle,  and  let  up  the  gas  in 
small  bubbles.  When  the  bubbles  come  in  con- 
tact with  the  blaze  of  the  turpentine  taper,  they 
will  explode,  exhibiting  the  cracking  of  musquet- 
ry,  firing  from  under  the  water. 

Rationale.  Hydrogen  and  carbon  being  both 
combustible  substances,  when  presented  to  pure 
oxygen  in  the  subtle  states  of  a  gas,  they  become 
inflamed  so  suddenly  as  to  cause  the  explosion. 

Application.  A  similar  gas  mixed  with  olifi- 
ant  gas,  is  sometimes  generated  in  coal  mines, 
which  coming  in  contact  with  the  oxygen  of  the 
air,  often  explodes  when  the  workmen  go  into  the 
pits  with  candles.  But  it  is  found,  that  if  the  can- 
dle is  enclosed  by  fine  wire  gauze,  called  Davy's 
safety  lamp,  the  gas  will  not  explode.  If  the  in- 
structor has  such  a  net,  the  class  will  be  highly 


PRINCIPLE  5.      CARBON.  115 

gratified  with  its  exhibition,  which  may  be  easily 
made  in  a  large  glass  jar  filled  with  the  mixture 
of  gases  just  mentioned. 

Prop.  10.     Carbon  and  hydrogen  may  be  unit 
ed,  forming  a  heavy  carburetted  hydrogen  gas? 
Killed  olifiant  gas,  by  heating  alcohol  and  sulphu 
ric  acid  together.     TJiis  is  called  the  white  gas., 
from  the  colour  of  its  flame. 

Illustration.  Put  half  a  wine-glass  of  alcohol 
in  to  a  deep  tubulated  retort,  pour  upon  it  in  a  small 
steady  stream  about  twice  as  much  by  measure  of 
strong  sulphuric  acid*  Put  in  the  stopper  and  ap- 
ply the  candle  to  the  retort,  approaching  it  gradu- 
ally. The  alcohol  at  first  becomes  somewhat 
charred  and  turns  black,  soon  afterwards  the  gas 
comes  over.  Let  a  little  of  the  first  escape,  which 
consists  of  atmospheric  air  and  ether.  Collect  the 
gas  over  water.  If  it  contains  considerable  sul- 
phurous acid  it  will  generally  disappear  soon 
while  standing  over  water  ;  but  lime  water  will 
entirely  purify  it,  if  necessary. 

Mix  it  with  double  its  volume  of  oxygen,  and 
explode  it  as  directed  with  the  light  carburetted 
hydrogen.  Also  burn  it  pure  in  a  stream,  as  di- 
rected in  burning  hydrogen  gas,  and  it  will  give  a 
very  luminous  blaze. 

Fill  a  glass  cylinder  or  opodeldoc  vial  with  li- 
quid chlorine.  Pass  this  gas  up  into  it,  until 
about  two  thirds  of  the  liquid  chlorine  is  displaced. 
The  volume  of  the  gas  will  be  diminished  on  stand- 
ing a  few  seconds^  and  water  will  ascend.  On 
the  surface  of  the  water  will  be  seen  oily  masses 
resembling  small  drops  of  tallow.  These  oily 
masses  give  the  name,  olifiant. 


ilB  CLASS   III.      OX1DABLES. 

Rationale.  The  rationale  for  the  light  cartm- 
retted  hydrogen,  applies  to  the  heavy  also,  with 
this  addition  :  Alcohol  being  a  vegetable  sub- 
stance, whose  chief  constituent  is  carbon,  the  ac- 
tion of  sulphuric  acid  chars  the  carbonaceous  part. 
This  imperfect  charcoal  is  of  a  soft  yielding  tex- 
ture, and  unites  more  freely  with  the  hydrogen. 
Thus  the  higher  definite  compound  is  produced. 

Application.  Both  the  formation  of  this  gas, 
when  the  alcohol  becomes  charred  and  its  pro- 
ducing an  oil  when  mixed  with  chlorine,  present 
a  curious  exhibition  of  changes  produced  upon 
vegetable  matter,  while  passing  through  different 
states  of  combination. 

Prop.  11.  Carbon  and  hydrogen  will  unite, 
yartly  as  in  the  light,  and  partly  as  in  the  heavy 
carburetted  hydrogen  gas,  by  distilling  pit  coal 
with  a  red  heat.  This  produces  the  gas  used  fov 
what  is  called  the  gas-light.  It  is  called  coal 
gas. 

Illustration.  Pulverize  some  pit-coal,  common- 
ly called  sea-coal,  and  heat  it  in  a  gun-barrel,  as 
directed  in  using  charcoal,  and  obtain  the  gas  ia 
the  same  manner,  with  the  following  exceptions  : 
Fit  a  piece  of  wood  in  the  form  of  a  half-cylin- 
der, so  that  it  will  fill  one  half  of  the  gun- barrel 
from  end  to  end.  Set  it  in  an  oblique  position 
\vith  the  empty  side  downwards,  and  in  this  posi- 
tion put  in  the  pulverized  coal,  so  as  to  fill  it  about 
one  third  of  its  length.  Now  put  it  into  the  fire 
with  the  same  side  downwards,  and  after  it  is 
placed  in  the  situation  in  which  it  is  to  remain, 
draw  out  the  piece  of  wood,  leaving  the  barrel  but 
half  filled.  When  the  heat  is  raised  the  coal  will 
and  fill  the  barrel,  which  it  would  burst  if 


PRINCIPLE    5.       CAIiBON.  117 

filled  at  first.  The  gas  will  soon  come  over  hi 
abundance,  and  briny;  over  with  it  great  quantities 
of  mineral  tar  and  bitumen.  It  should  stand  over 
water  several  hours  to  let  these  substances  sub- 
side. If  it  is  received  into  the  gasholder  of  the 
cistern,  the  water  must  be  drawn  off*,  the  cistern 
washed  and  filled  with  clean  water  before  it  is 
used  for  other  purposes.  The  gas  ma>  be  ex- 
ploded with  oxygen,  and  burned  in  a  stream,  as 
directed  with  light  carburetted  hydrogen.  The 
blaze  will  be  less  white  and  luminous  than  of  the 
olifiant  gas,  and  more  so  than  of  the  carburetted 
hydrogen. 

Rationale.  After  reading  the  rationale  of  the 
light  and  heavy  carburetted  hydrogen,  it  may  be 
added  ;  that  pit  coal  always  contains  a  sufficient 
proportion  of  water  in  combination  to  furnish  the 
necessary  proportions  of  hydrogen.  The  water 
being  chemically  combined  in  the  pit-coal,  the  gas 
comes  over  in  a  higher  state  of  combination  in 
part ;  constituting  a  mixture  of  the  light  and  the 
heavy  carburets. 

Application.  This  is  the  principle  on  which 
the  gas  for  the  gas-lights  is  obtained.  But  the  ap- 
paratus is  so  arranged  as  to  obtain  it  very  eco- 
nomically, and  purify  it  without  expense.  The 
mineral  pitch  is  preserved  for  useful  purposes  In 
London  seventy-six  thousand  lights  are  supported 
by  this  gas  with  28  chaldrons  of  coal  per  day. 
Messrs.  Taylors  of  England,  have  lately  contrived 
a  method  for  obtaining  a  gas  for  gas-lights  very 
economically  from  every  kind  of  oil. 

A  mixed  gas  consisting  of  different  proportions 
of  the  light  and  heavy,  constitutes  a  large  propor- 
tion of  the  fuel  of  our  wood  fires.  When  a  billet 


118  CLASS    III.      OXIDABLES. 

of  wood  is  laid  upon  the  fire  and  becomes  heated, 
the  water  of  the  wood  is  decomposed  by  the  car- 
bon, and  carburetted  hydrogen  gas  issues  from  it 
at  its  pores  and  cleavages.  Though  it  is  often 
mixed  with  steam,  it  takes  fire  and  burns  with  a 
flame  more  or  less  bright  according  to  its  propor- 
tions of  light  and  heavy  carburet.  Birch  bark, 
(or  rather  the  cuticle)  gives  out  the  heavy  carbu- 
retted hydrogen  almost  pure.  The  fla^ne  of  the 
gas  may  be  known  by  its  not  extending  down  to 
the  wood. 

PRINCIPLE  6.     BORON. 

Natural  History  and  general  Remarks. 

Boron  is  the  basis  of  boracic  acid.  The  acid 
is  found  in  the  East  Indies,  Persia,  Thibet,  &c. 
combined  with  soda  ;  forming  the  salt  called  bo- 
rax or  tinka!.  It  is  generally  found  in  lakes.  It 
gives  the  alkaline  test,  and  is  therefore  called  a 
sub  borate  of  soda. 

Boron  combined  with  oxygen  in  the  state  of  bo- 
racic acid,  is  united  to  a  base  of  soda,  forming  bo- 
rax, from  which  it  may  be  obtained  in  solid  scales 
by  elective  affinity. 

Illustration.  Dissolve  common  borax  in  about 
six  dates  its  bulk  of  hot  water  in  a  gallipot  Then 
pour  into  it  ab  nit  half  its  weight  of  sulphuric  acid. 
After  stirring  it  on  pretty  hot  coals  for  five  or  six 
minutes,  set  it  by  to  cool.  A  decomposition  takes 
place,  sulphate  of  soda  is  formed  which  remains 
in  solution,  and  the  boracic  acid  is  disengaged  and 
appears  in  solid  shining  scales  Pour  off  the  li- 
quid solution  of  sulphate  of  soda,  and  rince  the 
scales  several  times  in  cold  water.  Every  time 


]  RINCIPLE    7.       SELENIUM.  119 

wait  for  them  to  separate  from  the  water,  in  which 
they  can  hardly  he  dissolved.  When  well  wash- 
ed they  are  nearly  tasteless.  Now  dissolve  some 
of  the  boracic  acid  scales  in  alcohol  on  an  earthen 
plate,  and  set  the  alcohol  on  fire  with  a  lighted 
roll  of  paper,  and  as  it  hums,  the  points  and 
sides  of  the  flame  will  he  tinged  with  a  beautiful 
green. 

Rationale.  Soda  has  a  stronger  affinity  for  sul- 
phuric than  fir  boracic  acid.  But  the  difference 
is  not  great  enough  to  effect  a  ready  de<  omposi- 
tion  cold.  When  heat  is  applied,  the  decompo- 
sition is  effected.  The  new  compound,  sulphate 
of  soda,  is  soluble  in  water  moderately  cool,  in 
which  boracic  acid  is  solid.  This  diiiVrence  in 
the  solubility  of  the  two  substances  affords  the 
means  of  separating  them  as  given  in  the  last 
paragraph. 

Application.  This  experiment  exhibits  one 
mineral  acid  in  the  solid  state  when  pure.  The 
salt,  which  this  acid  forms  in  combination  with 
soda,  is  much  used  in  brazing,  under  the  name  of 
borax.  It  brings  brass  to  the  liquid  state  when 
thrown  upon  it,  at  a  temperature  considerably  be- 
low its  fusing  point.  Borax  becomes  a  soluble 
glass  after  parting  with  its  water  of  crystallization 
before  the  blow  pipe. 

PRINCIPLE  7.     SELENIUM. 

Natural  History  and  general  Remarks. 

Selenium  is  an  extremely  rare  substance ;  hav- 
ing been  found  by  Berzelius  in  very  minute  quan- 
tities in  pyrites  from  Fahlun,  in  Sweden.  It  re- 


120  CLASS    III.      OXLDABLES. 

sembles  sulphur  more  than  it  does  any  other  sub- 
stance ;  though  it  approaches  the  nature  of  tellu- 
rium.    It   is  reddish  in   minute  pieces  ;  but  its 
fracture  is  like  lead  in  larger  masses.     It  melts  a 
a  little  above  the  boiling  heat  of  water.     After 
melting,  it  becomes  soft  and  adhesive  like  wax. 
On    being   heated  more   highly  it  is  volatilized  in 
the  state  of  a  gaseous  oxid  of  the  odour  of  horse 
radish. 


121 

CLASS  IV.    METALLOIDS. 

General  Remarks. 

At  this  point  of  a  course  of  instruction  in  chem- 
istry, the  subject  takes  an  essential  change.  Pneu- 
matic chemistry  is  chiefly  terminated  here ; though 
not  wholly.  We  now  enter  upon  that  part  of  the 
course,  which  embraces  most  of  what  is  usually 
denominated  assaying.  The  preceding  and  fol 
lowing  parts  of  the  course  are  sometimes  given  in 
distinct  laboratories.  The  latter  often  requires 
very  high  heat  and  more  earthy  and  metallic  ap- 
paratus. Fewer  new  laws  are  introduced  with 
the  introduction  of  a  new  principle  There  is 
more  labor  and  less  science,  or,  as  some  would 
say,  more  of  art  and  less  of  science  presented  at 
every  succeeding  exercise.  Our  nomenclature 
must  be  further  explained  before  we  proceed. 
The  rationale,  as  a  distinct  paragraph,  will  not 
be  given  in  the  remainder  of  this  book.  Having 
been  so  far  instructed,  the  student  should  be  ex- 
ercised in  furnishing  his  own  rationale,  through 
the  remainder  of  the  course.  In  difficult  and  in 
doubtful  cases,  the  teacher  should  discuss  the  sub- 
ject in  his  lectures. 

NOMENCLATURE. 

When  a  salt  is  composed  of  a  base  united  with 
an  acid  in  its  highest  state  of  acidification,  the 
name  of  the  acid  ends  in  ate — if  the  acid  is  in  the 
lowest  state  of  acidification,  its  name  ends  in  ite. 
As  saltpetre  is  composed  of  nitric  acid  and  pot- 
ash, it  is  called  nitrate  of  potash — potash  and  ni- 
trous acid  would  be  called  nitrite  of  potash. 

11 


122  CLASS    IV.      METALLOIDS. 

Sometimes  the  state  of  the  oxidation  of  the  base 
is  expressed  by  prefixing  its  degree  to  the  name 
of  the  acid.  As  copperas  is  sulphuric  acid  com 
bined  with  the  protoxid  of  iron,  it  would  be  pro- 
to-sulphate  of  iron.  As  blue  vitriol  is  sulphuric 
acid  combined  with  the  deutoxid  of  copper,  it 
would  be  deuto- sulphate  of  copper. 

When  an  acidifiable  substance  is  united  to  a 
base  without  being  acidified,  it  ends  in  uret.  As 
sulphur  and  iron  melted  together  form  sulphuret 
of  iron — sulphur  and  potash,  sulphuret  of  potash, 
When  the  compounds  are  both  acidifiable  substan- 
ces not  metallic  or  in  the  state  of  gas,  uretted  is 
generally  the  termination.  As  phosphuretted  hy- 
drogen gas,  sulphuretted  hydrogen  gas,  carburet- 
ted  hydrogen  gas. 

When  two  or  more  metals  are  combined,  they 
are  called  alloys  ;  unless  one  of  the  metals  is  mer- 
cury, when  the  mixture  is  called  an  amalgam. 
When  a  metal  is  combined  with  any  substance, 
excepting  another  metal,  it  is  said  to  be  mineraliz- 
ed with  it.  This,  however,  is  a  term  appertaining 
rather  to  mineralogy  than  to  chemistry. 

SECTION  I.     BASES  OF  ALKALIES  AND  OF  ALKA- 
LINE EARTHS. 

General  Remarks. 

It  is  now  established,  that  these  alkalies  consist 
of  peculiar  bases,  united  to  oxygen.  These  bases 
have  some  properties  in  common  with  metals;  but 
they  differ  so  widely  in  other  properties,  particu- 
larly in  their  specific  gravity,  that  they  are  de- 
nominated metalloids.  The  oxygen  may  be  sepa- 
rated from  the  bases  by  a  very  powerful  galvanic 


PRINCIPLE    1.       OF   POTASH.  123 

battery,  and  some  of  them  by  other  means.  And 
though  such  experiments  are  brilliant  and  very 
amusing,  they  have  no  practical  application  to  the 
purposes  of  life.  They  would  be  introduced  here, 
however,  as  well  calculated  to  illustrate  principle^ 
were  they  not  attended  with  too  much  difficulty 
and  expense  for  the  course  proposed  in  this  work. 
The  alkalies  and  alkaline  earths  consist  of  pe- 
culiar metalloidal  bases,  chemically  combined  with 
definite  proportions  of  oxygen.  They  all  give 
the  common  alkaline  tests.  That  is,  they  give  a 
green  colour  to  blue  and  generally  to  red  vegeta- 
ble infusions  ;  such  as  of  red  cabbage,  blue  and 
purple  petals  of  violets,  &c.  They  are  all  caus 
tic  to  the  taste.  They  constitute  the  bases  of  ma- 
ny important  salts,  both  natural  and  artificial,  as 
will  be  shown  under  each  of  them  respectively. 

PRINCIPLE  1.     OF  POTASH. 

Natural  History  and  general  Remarks. 

As  potash  is  one  of  the  constituents  of  felspar, 
a  homogeneous  mineral  aggregated  with  quartz 
and  mica  in  granite)  it  exists  in  the  oldest  of  the 
primitive  rocks,  as  well  as  in  animals  ami  vegeta- 
bles. It  is  chiefly  obtained  by  lixiviation  from 
the  ashes  of  burned  vegetables.  It  is  also  a  very 
abundant  production  of  nature  in  the  state  of  the 
basis  of  saltpetre. 

Prop.  1.  Potash  may  be  obtained  tolerably  pure 
by  abstracting  the  carbonic  acid  from  pearlash  by 
the  aid  of  quick  lime. 

Illustration.  Dissolve  pearlash  in  about  twice 
its  weight  of  boiling  water.  Mix  this  with  about 
as  much  newly  slacked  quick  linie.  Let  this  stand 


124  CLASS    IV*      METALLOIDS. 

about  a  week  corked  closely  in  a  bottle,  occasion- 
ally shaking  the  mixture.  At  last  let  the  lime  set- 
tle to  the  bottom,  and  carefully  pour  off  the  super- 
natant liquid,  which  is  the  pure  caustic  potash  in 
solution.  But  if  it  be  wanted  for  immediate  use, 
boil  the  mixture  about  an  hour  in  an  iron  kettle, 
adding  water  enough  to  keep  it  in  the  state  of  a 
cream-like  liquid,  and  the  decomposition  will  be 
effected.  If  the  potash  is  wanted  in  a  crystallized 
state,  evaporate  the  liquid  very  slowly,  just  keep- 
ing the  steam  rising  frotu  it. 

Application.  Pearlash,  the  sub-carbonate  of 
potash,  is  made  while  a  high  heat  is  applied.  Con- 
sequently vegetable  impurities  and  most  substan- 
ces contained  in  common  potash  are  driven  out. 
[Now  the  carbonic  acid  being  withdrawn  also,  the 
potash  is  left  nearly  pure  and  severely  caustic. — 
A  quantity  should  always  be  in  readiness  in  the 
laboratory,  both  liquid  and  solid. 

Prop.  2.  Potash  has  a  strong  affinity  for  all 
animal  matter. 

Illustration.  Melt  a  little  common  potash  in 
an  iron  ladle,  then  put  into  it  small  bits  of  fresh 
meat  and  woollen  rags  and  boil  them  a  short  time. 
The  rags  and,  meat  will  be  dissolved  and  soap  will 
be  formed. 

Application.  On  this  principle  soap  is  made 
by  boiling  any  animal  substance  with  ley,  which 
is  a  solution  of  potash.  It  requires  very  strong 
ley,  or  rather  melted  potash,  to  convert  rags  and 
some  other  animal  substances  into  soap.  As  pot- 
ash readily  becomes  diliquescent,  as  shewn  by  nu- 
merous experiments,  soap  is  always  soft  or  in  the 
state  of  an  imperfect  liquid  when  potash  is  used. 


PRINCIPLE    1.      OF  POTASH.  125 

Prop.  3.  Potash  will  unite  directly  with  sul- 
phur, and  form  sulphuret  of  potash. 

Illustration.  Take  some  dry  pearlash  and  half 
as  much  sulphur,  mix  them  and  rub  them  well  to- 
gether. Melt  them  together  in  a  crucible  covered 
with  another  crucible,  as  directed  in  making  sul- 
phuret  of  iron,  excepting  that  it  must  be  poured 
out  when  melted.  It  must  also  be  corked  up  in  a 
vial  to  prevent  its  diliquescing. 

Application.  Sulphuretted  hydrogen  gas  may 
be  made  with  this,  as  with  the  sulphuret  of  iron. 
It  is  also  used  in  medicine,  and  was  called  liver 
of  sulphur  or  hepar  sulphuris. 

Prop.  4.  Potash  may  be  combined  with  nitric 
acid,  and  form  nitrate  of  potash,  called  saltpetre. 

Illustration.  Fill  a  tumbler  half  full  of  diluted 
nitric  acid,  consisting  of  one  part  of  nitric  acid  to 
six  parts  of  water,  firop  in  pearlash,  a  little  at  a 
time,  to  the  point  of  saturation  ;  that  is,  until  if 
ceases  to  effervesce.  This  will  be  the  nitrate  of 
potash  in  solution.  Now  if  it  is  wanted  in  the 
state  of  crystals,  evaporate  it  as  heretofore  direct- 
ed. 

Application.  Saltpetre  is  found  in  abundance 
in  nature,  combined  with  a  little  common  salt ; 
therefore  it  is  never  made  in  this  way,  excepting 
by  way  of  experiment. 

Prop.  5.  Nitrate  of  potash  may  be  reduced  to 
the  nitrite  of  potash  by  heating  it. 

Illustration.     Throw  saltpetre  upon  hot  coals. . 
The  coals  will  burn  brilliantly  a  short  time.  Some 
of  the  residue  of  the  saltpetre  may  be  scraped 
from  the  coajs,     This  is  the  nitrite  of  potash,  and 

41* 


126  CLASS    IV.      METALLOIDS. 

will  not  cause  the  brilliant  combustion  of  coals ; 
because  the  highest  proportion  of  oxygen  is  elim- 
inated from  the  acid  and  the  lower  proportions 
are  held  by  stronger  affinity. 

Application.  The  use  of  saltpetre  in  the  man- 
ufactory of  gunpowder  depends  on  the  easy  dis- 
engagement of  the  highest  proportion  of  oxygen 
from  its  nitric  acid.  The  oxygen  being  in  imme- 
diate contact  with  the  combustible  ingredients  of 
the  gunpowder  (charcoal  and  sulphur)  these  sol- 
ids suddenly  become  elastic  gases. 

Prop.  6  Potash  combined  with  an  acid  in  the 
definite  proportion  which  constitutes  a  neutral 
salty  causes  no  change  in  the  colour  of  vegetable 
Hues  ;  but  when  the  proportion  is  varied,  changes 
are  produced. 

Illustration.  Dissolve  a  piece  of  saltpetre,  of 
the  size  of  half  a  pea,  in  a  wine-glass  of  pure  wa- 
ier,  Four  a  little  of  it  into  another  glass,  contain- 
ing the  blue  infusion  of  red  cabbage ;  and  no  change 
of  colour  will  be  produced.  Add  a  drop  from  a 
weak  solution  of  potash,  to  the  saltpetre  solution, 
and  it  will  now  change  the  cabbage  infusion  to 
green.  If  dilute  nitric  acid  be  added  gradually 
to  the  saltpetre  solution,  and  stopped  at  the  pre- 
cise point  of  saturation,  it  will  not  change  the  co- 
lour of  the  infusion.  But  ever  so  small  a  quantity 
of  the  acid  in  exbess  will  produce  a  red  colour. 
Thus  the  saltpetre  solution  may  be  made  to  give 
red  and  green  colours  to  the  infusion,  alternately^ 
any  number  of  times. 

The  same  experiment,  if  performed  with  any 
neutral  salt,  and  the  alternate  additions  of  its  acid 
and  base;  will  produce  the  same  xesult. 


PRINCIPLE    1.      OF  POTASH.  127 

Application.  When  clothes  are  spotted  with 
acids  or  alkalies,  neutral  salts  may  be  produced  on 
the  cloth,  and  the  ill  effects  prevented,  if  attend- 
ed to  immediately.  Thus  if  a  black  coat  be  spot- 
ted with  sulphuric  acid,  any  of  the  alkalies  will 
extinguish  the  spot  by  neutralizing  the  acid. — 
Pearlash,  or  some  other  sub-carbonate,  is  prefer- 
able to  the  strong  alkalies.  The  spot  where  the 
.application  is  made  must  be  washed  immediately 
with  pure  water. 

Rein  irk.  The  infusion  of  red  cabbage  only  is 
mentioned  above  as  the  test  for  acids  and  alka- 
lies ;  though  blue  violets,  elder  berries,  and  sev- 
eral other  vegetable  substances  may  be  used. — 
These  infusions  are  sure  tests,  excepting  that  wa- 
ter, charged  with  sulphuretted  hydrogen,  will 
change  them  to  red,  like  acids. 

Prop.  7.  Salts  of  potash  are  insoluble  in  pure 
alcohol. 

Illustration.  Drop  a  hard  lump  of  pearlash 
into  good  alcohol,  and  it  will  remain  in  the  solid 
state  any  length  of  time. 

Application.  The  common  alcohol  of  the  shops 
always  contains  considerable  water.  If  perfectly 
dry  pearlash  is  put  into  it,  some  of  it  will  be  dis- 
solved by  the  water.  The  nearly  pure  superna- 
tant alcohol  may  then  be  poured  off  for  use. 

Prop.  8.  Potash  may  be  combined  with  chlo- 
rine, or  oxymuriatic  acid,  and  form  the  oxymuri- 
ate  of  potash. 

Illustration.  Fill  a  two  quart  bladder  with 
chlorine,  oroxymuriatic  acid  gas.  Fit  to  the  stop- 
cock of  the  bladder  a  small  glass  tube.  Dissolve 
about  an  ounce  and  a  half  of  pearlash  in  a  pint  of 


128  CLASS    IV.      METALLOIDS. 

water,  and  put  it  into  a  receiver.  Immerse  the 
end  of  the  tube  in  the  solution,  and  close  the  tu- 
bulature  where  it  enters  with  beeswax.  Lay  a 
light  weight  upon  the  bladder,  which  will  press 
it  gently,  and  turn  the  stop  so  as  to  let  out  a  very 
minute  stream  of  the  gas,  so  small  that  the  whole 
shall  not  run  out  in  less  time  than  an  hour  or  two. 
Let  the  receiver  be  almost  air  tight,  leaving  only 
a  hole  a  little  larger  than  a  pin  in  the  wax  by  the 
side  of  the  tube  where  it  enters  the  receiver,  for 
the  carbonic  acid  to  escape,  which  will  be  driven 
from  its  connexion  with  the  pearlash.  After  the 
gas  is  all  pressed  out  of  the  bladder,  draw  out  the 
tube,  close  up  the  receiver,  and  place  it  in  a  cool 
dark  cellar.  After  a  day  or  two,  crystals  of  oxy- 
Wiuriate  of  potash  will  be  found  deposited  in  the 
bottom  of  the  receiver.  Pour  off  the  liquid,  scrape 
out  the  crystals  arid  drain  them.  They  must  then 
be  dissolved  in  considerable  hot  water.  Set  it 
away  to  cool,  and  the  crystals  will  be  formed 
again,  which  may  be  drained,  dried,  and  put  up 
in  a  vial  for  use. 

Application.  This  preparation  will  explain 
much  of  the  doctrine  of  affinity,  &c.  to  the  opera- 
tor ;  but  so  little  of  it  can  be  performed  while  big 
class  is  present^  that  it  is  preferable  to  purchase 
this  salt  of  those  who  manufacture  it  in  the  large 
way  in  Woulf?s  apparatus. 

Prop.  9.  Oxymuriate  of  potash  will  communi- 
cate oxygen  to  some  combustible  substances  by  com- 
pression, sufficient  to  inflame  them  and  to  produce 
explosion. 

Illustration.  Scatter  some  thin  shavings  of 
phosphorus  over  the  bottom  of  a  broad  iron  mortar. 
Hpriukle  crystals  of  oxymuriate  of  potash  among 


PRINCIPLE  1.      OF  POTASH.  129 

them.  Now,  putting  a  leathern  glove  upon  the 
hand,  rub  the  iron  pestle  smartly  around  among 
the  shavings  of  phosphorus,  and  a  succession  of 
explosions  will  be  made,  resembling  the  irregular 
discharges  of  militia  musketry.  It  is  probable 
that  these  explosions  are  caused  by  the  sudden 
conversion  of  two  solids  into  vapour.  Oxygen  is 
combined  in  the  salt  in  the  solid  state.  Phospho- 
rus is  also  a  solid.  By  being  closely  compressed^ 
they  instantly  become  phosphoric  acid  in  a  va- 
pourous  state. 

Application.  To  the  same  principle  all  explo- 
sive powders  owe  their  powers.  Gunpowder  is 
essentially  composed  of  about  75  per  cent  of  ni- 
trate of  potash,  15  per  cent  of  charcoal,  and  10  per 
cent  of  sulphur.  These  substances  are  finely  pul- 
verized separately,  and  then  intimately  mixed. 
The  nitric  acid  of  the  nitrate  of  potash,  on  being 
inflamed,  parts  with  so  much  of  its  oxygen  as  to 
be  reduced  to  nitric  oxid  gas,  and  part  of  it  to  ni- 
trogen gas.  In  doing  this,  oxygen  is  furnished  to 
the  charcoal  sufficient  to  convert  it  into  carbonic 
acid  gas,  and  to  the  sulphur  to  convert  it  into  sul 
phurous  acid  gas  These  solid  constituents  of  gun- 
powder, springing  suddenly  into  the  state  of  these 
four  gases,  expand  their  volume  to  such  a  vast  ex- 
tent, as  to  produce  a  violent  concussion  upon  the 
atmosphere,  and  to  impel  a  leaden  ball,  or  other 
opposing  body,  with  great  velocity. 

The  same  principle  may  be  further  illustrated 
by  finely  pulverizing  and  rubbing  well  together 
three  parts  of  dried  saltpetre,  two  of  well  dried 
pearlash,  and  one  of  sulphur.  Melt  the  mixture 
in  an  iron  ladle,  with  a  degree  of  heat  a  little  below 
the  red  heat  of  iron  5  and  immediately  after  melt* 


130  CLASS    IV.      METALLOIDS. 

ing,  the  mixture  will  explode  with  violence.  Here 
the  three  solid  substances  spring  into  several  gases 
on  the  same  principle  as  before  explained. 

PRINCIPLE  2.     OF  SODA. 
Natural  History  and  general  Remarks. 

Soda  often  constitutes  a  part  of  felspar.  There- 
fore, like  potash,  it  is  contained  in  the  oldest  pri- 
mitive rocks.  It  is  found  in  animals  and  vegeta- 
bles ;  but  is  not  so  abundant  in  vegetables  as  pot- 
ash. It  is  very  abundant  in  nature  as  the  basis  of 
common  salt.  For  commerce  it  is  mostly  obtain- 
ed by  lixiviation,  from  the  ashes  of  burned  sea- 
weeds, and  sold  under  the  name  of  barilla.  It  is 
sometimes  called  natron. 

Soda  has  many  properties  in  common  with  pot- 
ash. It  gives  the  alkaline  test,  is  obtained  pure 
in  the  same  manner,  unites  with  acids,  animal 
matter,  &c.  But  its  affinity  for  the  acids  and  ani- 
inal  matter,  is  more  feeble ;  and  it  does  not  dili- 
quesce  by  attracting  vapour  from  the  atmosphere. 
Combined  with  oils  it  forms  hard  soap,  whereas 
potash  always  forms  soft  soap. 

Prop.  I.  Soda  may  be  combined  with  muriatic 
acid,  and  form  common  table  salt,  muriate  of  soda. 

Illustration.  Put  muriatic  acid  in  a  tumbler, 
diluted  with  about  six  times  its  measure  of  water. 
Drop  in  carbonate  of  soda  till  effervescence  ceases. 
Proceed  in  all  respects  as  directed  in  making  salt- 
petre. Pass  some  of  the  solution  among  the  class, 
and  they  will  recognize  the  table  salt. 

Application.  This  salt  is  found  so  abundant 
in/ nature,  that  it  is  never  produced  in  this  way. 
excepting  for  the  purpose  of  shewing  its  constitu 


PRINCIPLE  2.      OF  SODA.  131 

ents.     The  ocean  abounds  in  it,  the  western  salt- 
springs,  the  mines  of  Poland,  &c. 

Prop.  2.     Common  salt  may  be  decomposed  bij 
potash,  and  soda  obtained. 

Illustration.  Dissolve  an  ounce  of  common  salt 
(muriate  of  soda)  in  hot  water.  Add  three  fourths 
of  an  ounce  of  common  potash.  Keep  the  solu- 
tion at  a  moderate  heat  until  it  is  evaporated  to 
dry  ness.  Let  it  he  evaporated  on  a  broad  plate 
that  it  may  be  very  thinly  spread  over  the  bottom, 
Now  expose  it,  in  the  open  plate,  to  the  atmos- 
phere a  <hiy  or  two,  and  the  muriate  of  potash  will 
diliquesce,  while  the  soda  will  assume  the  form  of 
powder,  or  dust. 

Application.  Dissolve  good  soft  soap  by  heat- 
ing it  in  a  clean  tin  basin  with  about  twice  its  mea- 
sure of  rain  or  river  water.  Then  put  in  about 
half  a  gill  of  fine  common  salt  to  a  quart  of  this 
solution.  The  muriatic  acid  of  the  salt  will  unite 
with  the  potash  of  the  soap,  and  leave  the  soda  of 
the  salt  to  unite  with  the  oil  of  the  soap.  This 
latter  compound  after  a  little  boiling,  will  become 
somewhat  dense  and  float  on  the  surface  of  the  li- 
quid. On  draining  out  the  liquid,  which  is  chiefly 
muriate  of  potash,  and  drying  the  floating  com- 
pound, the  latter  will  be  found  to  be  common  hard 
soap. 

Thus  soap-boilers  make  the  common  hard  soap. 
The  liquid  muriate  of  potash  they  call  waste-ley 
or  dead-ley.  The  fine  hard  soap  is  made  direct- 
ly from  the  barilla  or  kelp,  which  is  a  rough  sub- 
carbonate  of  soda  made  from  the  leached  ashes  of 
sea- weeds. 

Prop.  3.  tioda  may  be  combined  with  sulphuric 
acid  and  form  Glauber's  salts. 


132  CLASS   IV.      METALLOIDS. 

Illustration.  Put  some  sulphuric  acid  into  a 
tumbler,  diluted  with  six  times  as  much  water. 
Drop  in  carbonate  of  soda,  until  effervescence 
ceases  Now  pass  some  of  the  liquid  in  wine 
glasses  and  the  members  of  the  class  will  recog- 
nize the  nauseous  taste  of  Glauber's  salts.  It 
may  be  crystallized  by  slow  evaporation  in  the 
usual  way. 

Application.  This  salt  is  produced  for  the 
shops  at  the  manufactories  of  muriatic  acid.  For 
the  sulphuric  acid  which  is  poured  upon  common 
salt  to  disengage  the  muriatic  acid,  combines  with 
the  soda  of  the  salt,  and  forms  sulphate  of  soda. 
After  purifying,  it  is  sold  to  the  druggists. 

PRINCIPLE  ?     OF  AMMONIA. 
Natural  History  and  general  Remarks. 

This  substance  is  one  of  the  compounds  under 
Nitrogen.  But  it  was  referred  to  this  place  for  a 
description  of  its  properties,  on  account  of  its  near 
relation  to  the  fixed  alkalies.  This  is  usually  call- 
ed the  volatile  alkali.  On  account  of  its  salts 
forming  with  mercury,  under  galvanic  influence, 
a  compound  resembling  the  amalgams  of  mercury 
and  other  metals,  Berzelius  supposed  it  might  be 
a  metal,  to  be  called  ammonium.  As  ammonia  is 
known  to  be  a  compound,  and  as  it  forms  an  amal- 
gam with  mercury,  it  goes  far  towards  proving 
that  potassium,  sodium,  &c.  are  compound  bodies. 
The  proof,  however,  is  of  that  kind,  called  ana- 
logy. And  there  is  some  want  of  correct  analogy; 
though  it  has  a  stronger  bearing  upon  the  subject, 
than  that  upon  which  the  hypothesis  of  the  basis 
of  alumine  is  founded. 


PRINCIPLE   ?.       OF   AMMONIUM.  133 

It  seems  to  be  proved  by  Gay  Lussac,  that  it 
consists  of  75  per  cent  of  hydrogen  and  25  per  cent 
of  nitrogen. 

It  is  mostly  found  in  the  state  of  sal  ammoniac 
(the  muriate  of  ammonia)  in  Egypt.  It  is  chiefly 
manufactured  hy  the  lixiviation  process  from  the 
excrements  of  animals  which  feed  on  plants  grow- 
ing near  salt  water.  It  ha,s  been  found  near  several 
extinct,  or  nearly  extinct,  volcanoes.  The  pure 
gaseous  ammonia,  and  the  various  salts,  are  obtain- 
ed from  the  muriate. 

Prop.  I.  Ammonia  is  obtained  in  the  state  of 
gas  from  sal  ammoniac 'by  elective  affinity. 

Illustration.  Pulverize  a  table  spoonful  of  sal 
ammoniac,  (muriate  of  ammonia)  and  put  the  dry 
powder  into  a  half  pint  retort.  Put  in  with  it 
about  twice  as  much  fine  quicklime.  Now  mix 
them  well  by  shaking  the  retort.  Having  luted 
on  a  pipe-bowl,  with  half  an  inch  of  the  stem,  up- 
on the  beak  of  the  retort,  as  directed  in  obtaining 
muriatic  acid  gas  and  for  the  same  reason ;  now 
immerse  the  beak  in  the  mercurial  trough,  and  ap 
ply  the  heat  of  a  candle  to  the  retort.  The  ammo- 
niacal  gas  will  immediately  o.ue  over.  Let  it  es- 
cape a  little  while,  that  the  atmospheric  air  may 
be  driven  out.  Now  collect  it  as  directed  in  col 
lecting  muriatic  acid  gas. 

Application.  Hartshorn  vials  may  be  prepared 
upon  this  principle.  Put  pulverized  sal  ammoni- 
ac and  quicklime  into  a  vial  and  cork  it  closely. 
Whenever  the  scent  of  the  ammonia  is  wanted, 
shake  the  mixture  before  pulling  out  the  cork. 
The  same  effect  will  be  produced  by  rubbing  dry 
quicklime  upon  the  surface  of  a  piece  of  sal  ammo- 
niac, and  applying  it  to  the  nose,  la  all  these 

12 


134  CLASS    IV.      METALLOIDS. 

experiments,  the  muriatic  acid  of  the  muriate  of 
ammonia  elects  the  lime,  and  the  ammonia  is  dis- 
charged ;  and  ammonia  when  pure  is  in  the  state 
of  gas. 

Prop.  2.  Ammonia  extinguishes  flame  after  a 
momentary  enlargement  of  it,  and  destroys  life 
when  breathed. 

Illustration.  Immerse  a  short  piece  of  a  hum- 
ing  candle  in  a  small  cyliridric  glass  of  the  gas. 
The  blaze  will  he  enlarged  a  little  for  an  instant 
and  then  he  extinguished.  Put  a  mouse  into  it 
and  it  will  soon  expire. 

Application.  Though  the  action  of  this  gas,  by 
stimulating  the  olfactory  nerves,  revives  a  fainting 
patient ;  yet  it  will  destroy  life  if  respired  several 
times.  If  oxy muriatic  acid  is  inhaled  by  accident, 
let  some  ammoniacal  gas  be  instantly  inhaled  after 
it,  and  it  will  correct  its  destructive  effects.  The 
two  gases  probably  form  an  imperfect  oxymuriate 
of  ammonia  in  the  lungs.  That  this  effect  is  pro- 
duced, I  had  an  opportunity  to  demonstrate  by 
most  painful  experience,  while  giving  a  course  of 
lectures  in  the  capitol,  before  the  New- York  state 
legislature. 

Prop.  3.  Jlmmonia  in  the  state  of  gas,  will  unite 
with  muriatic  acid  gas9  and  with  carbonic  acid 
gas  ;  and  with  the  former  produce  the  solid  mu- 
riate, and  with  the  latter  the  solid  carbonate  of  am- 
monia. 

Illustration.  Produce  carbonic  acid  gas  in  the 
common  way  and  ammoniacal  gas  as  before  di- 
rected. Let  the  two  gases  meet  in  the  same  globe 
receiver  at  different  apertures,  or  at  opposite  ends 
of  a  cylinder  or  adopter,  and  the  receiver  will  soon 


PRINCIPLE   ?.      OF    AMMONIUM,  135 

be  lined  with  carbonate  of  ammonia.  If  muriatic 
acid  be  substituted  for  carbonic,  the  muriate  of 
ammonia  will  be  produced.  Or  fill  two  small  glass 
cylinders  balf  full  of  ammoniacal  gas  over  mercu- 
ry. Pass  muriatic  acid  gas  into  one  from  a  vial 
which  is  small  enough  to  turn  under  the  cylinder, 
and  carbonic  acid  gas  into  the  other.  Both  cylinders 
will  be  lined  with  thin  layers  of  salt,  and  the  mer- 
cury will  ascend  to  fill  the  vacancy.  On  passing 
the  cylinders  among  the  class  with  tasting  rods, 
they  will  recognize  the  sal  ammoniac  (muriate  of 
ammonia)  in  one,  and  the  salts  of  hartshorn  (car- 
bonate of  ammonia)  in  the  other.  Lest  some  of  the 
class  should  not  recollect  the  taste  of  these  salts, 
it  will  be  best  to  pass  around  specimens  of  each 
\vith  the  cylinders. 

Application.  These  salts  are  not  manufactured 
in  this  manner  for  the  shops.  The  muriate  of  am- 
monia is  produced  in  nature.  The  carbonate  of 
ammonia  is  manufactured  by  heating  chalk,  (car- 
bonate of  lime)  and  muriate  of  ammonia  together. 
A  double  decomposition  takes  place  ;  carbonate  oi* 
ammonia  arid  muriate  of  lime  are  formed. 

The  experiments  described  in  this  illustration 
exhibit  the  reduction  of  gases  to  the  solid  state  as 
clearly  as  any  experiment  of  the  laboratory. 

Prop.  4.  Carbonate  of  ammonia  may  be  manu- 
factured by  double  elective  affinity,  with  carbonate 
of  lime  and  muriate  of  ammonia. 

Illustration.     Put  into  a  florence  flask,  or  a  re 
tort,   dry  pulverized  chalk   (carbonate  of  lime) 
with  half  as  much  sal  ammonia,  (muriate  of  am- 
monia.)    Heat  the  flask  in  a  lead  pot,  and  dry 
carbonate  of  ammonia  will  be  sublimed  and  line 


136  CLASS    IV,       METALLOIDS. 

the  neck,     The  heat  must  be  considerable,  some- 
limes  requiring  the  retort  to  be  coated  with  clay. 

Application.  Carbonate  of  ammonia  is  prepar- 
ed in  this  manner  for  accurate  experiments  in  the 
laboratory  only.  For  commerce,  it  is  prepared 
upon  the  same  principle,  but  in  a  coarser  manner. 

Prop.  5.  Ammonia  may  be  combined  with  ni- 
tric avid,  and  nitrate  of  ammonia  be  formed. 

Illustration.  Put  nitric  acid  into  a  tumbler  di- 
luted with  about  six  times  as  much  water.  Drop 
Into  it  coarsely  pulverized  carbonate  of  ammonia 
until,  effervescence  ceases  ;  or  until  pieces  of  the 
carbonate  will  fall  to  the  bottom  without  efferves- 
cence. A  solution  of  nitrate  of  ammonia  will  then 
be  formed.  If  it  be  required  in  Crystals,  evapo- 
rate it  slowly,  until  a  drop  spread  on  cold  glass  is 
instantly  crystallized.  Then  set  it  by  to  cool,  and 
crystals  will  form  on  the  top.  Pour  out  the  li- 
quid part  and  evaporate  it  more,  and  so  on  as  be- 
fore directed.  If  the  dry  salt  is  required,  evapo- 
rate it  with  a  degree  of  heat  a  little  below  boiling, 
until  the  salt  is  dry,  without  removing  it  from  the 
fire. 

Application.  This  salt  is  chiefly  employed  for 
the  purpose  of  procuring  the  nitrous  oxid  or  ex- 
hilarating gas.  It  is  much  the  best  fur  that  use, 
to  dry  the  salt  down  without  crystallizing.  Or  if 
it  is  first  made  in  crystals,  it  ought  to  be  melted 
and  dried  down  in  open  plates,  before  it  is  used. 
But  if  it  is  dried  with  a  degree  of  heat  as  high  as 
the  boiling  point,  considerable  of  the  salt  will  be 
lost. 

,  Prop.  6.  Ammonia  is  strongly  absorbed  by  wa- 
ter^ forming  the  liquid  ammonia. 


PRINCIPLE    ?.      OF   AMMONIUM.  13? 

Illustration.  Pour  from  a  vial  a  little  cold  wa- 
ter under  a  glass  cylinder  of  ammoniac al  gas 
standing  over  mercury.  It  will  rapidly  absorb 
the  gas,  and  the  mercury  will  ascend  to  fill  the 
vacancy. 

Put  newly  slacked  lime  into  a  tubulated  retort 
which  had  been  previously  luted  into  a  receiver, 
and  set  in  a  suitable  lead  pot.  Put  in  about  two- 
thirds  as  much  pulverized  muriate  of  ammonia. 
!Now  put  in  water,  about  six  times  the  weight 
(call  a  pint  a  pound)  of  the  muriate  of  ammonia. 
The  muriatic  acid  will  elect  the  lime  as  before  ob- 
served, and  the  ammonia  will  be  discharged  ;  but 
it  will  immediately  lie  arrested  by  the  water,  form- 
ing the  liquid  ammonia,  called  also  spirits  of  harts- 
liorn  and  aqua  amnonia  But  being  combined 
with  the  newly  formed  muriate  of  lime  and  some 
lime  water,  it  must  be  distilled  over.  Raise  the 
heat  moderately  by  applying  the  hand  bellows  to 
the  coals  in  the  lead  pot  ;  at  the  same  time  s,ur* 
round  the  receiver  with  snow  or  cold  water.  Con- 
tinue the  process  until  the  liquid,  condensed  in 
the  receiver,  is  equal  in  measure  to  about  one  third 
of  the  water  put  in. 

Pure  ammoniacal  gas  may  be  disengaged,  with- 
out any  water,  by  duly  regulating  the  temperature, 
either  during  the  above  process  or  from  the  aqua 
ammonia  of  the  shops. 

Application.  The  first  experiment  proves,  that 
as  water  absorbs  ammonia,  which  is  the  basis  of 
many  impure  gases  that  arise  from  putrid  sub- 
stances, falling  rains  cleanse  the  atmosphere  by 
carrying  such  impure  effluvia  to  the  earth,  where 
they  serve  to  nourish  vegetation,  The  last  ex- 

12* 


138  CLASS    IV.      METALLOIDS. 

pcriraeut  is  an  exhibition  of  the  method  of  pre 
paring  the  aqua  ammonias  of  the  shops, 

Prop.  7.  Liquid  ammonia  will  unite  with  sul- 
phuretted hydrogen  gas,  and  form  the  hydro-sul- 
'pliuret  of  ammonia. 

Illustration.  Let  a  stream  of  sulphuretted  hy- 
drogen gas  pass  into  a  vial  of  liquid  ammonia. 
The  best  method  is  to  put  the  ammonia  into  a 
broad  mouthed  vial,  filling  it  about  half  full. — 
Turn  the  vial  in  an  oblique  position  and  extend 
the  beak  of  the  retort  to  the  bottom  of  it.  Wet 
tow  may  be  wound  about  the  neck  of  the  retort 
where  it  enters  the  mouth  of  the  vial  to  prevent 
the  escape  of  the  gas  ;  or  if  a  little  does  escape 
it  is  immaterial,  for  the  class  ought  to  become  suf- 
ficiently acquainted  with  this  gas  to  be  able  to  de- 
tecrit  by  the  smell.  Now  pour  some  of  the  liquid 
Into  a  solution  of  copperas  and  another  of  blue 
vitriol. 

Application.  This  is  the  most  universal  test 
for  the  metals  known  to  chemists.  It  precipitates 
all  metallic  solutions  with  such  different  colours, 
•when  applied  as  a  test,  that,  with  collateral  tests, 
almost  any  metal  may  be  detected.  For  many 
metals  it  is  a  perfect  test.  It  may  be  added  that 
all  the  other  alkalies  will  form  hydro-sulphurets 
also.  But  ammonia  forms  the  most  delicate  test 
and  is  generally  used. 

Prop.  8.  Ammonia  may  be  decomposed  and  re- 
duced to  its  constituent  elements  by  heat.  See 
Prop.  9.  under  Nitrogen. 

Illustration.  Put  quick  lime  and  sal  ammoniac 
into  a  florence  flask,  as  before  directed  in  produc- 
ing ammonia.  Fit  a  long  tobacco  pipe,  (a  small 


PRINCIPLE   3.      OF  LIME.  139 

iron  tube  will  do)  perfectly  tight  into  the  mouth  of 
the  flask.  Pass  the  pipe  through  a  lead  pot,  near 
its  middle.  Attach,  so  as  to  be  tight,  to  the  op- 
posite end  of  the  pipe,  a  glass  or  lead  tube,  bent 
down  into  a  bowl  of  water.  Raise  the  heat  in  the 
lead  pot,  until  the  pipe  is  red  hot.  Then  com- 
mence heating  the  flask  with  a  candle.  As  the 
ammoniacal  gas  is  disengaged  and  passes  through 
the  red  hot  pipe,  it  will  be  decomposed,  and  its 
two  constituent  gases,  hydrogen  and  nitrogen, 
will  pass  into  the  bowl  of  water,  where  it  may  be 
collected  in  small  vials. 

To  test  the  received  gases,  pour  them  into  a  long 
slender  tube.  A  long  test  glass  will  do.  Let 
them  stand  about  half  an  hour,  and  they  will  sepa- 
rate— the  hydrogen  rising  to  the  top.  Pour  small 
portions  at  a  time  into  a  very  small  test  glass  and 
let  down  a  minute  burning  taper  into  it.  Do  this 
several  times.  The  nitrogen  being  at  the  bottom, 
the  taper  will  be  extinguished  at  first.  At  last 
the  hydrogen  will  show  itself  by  burning. 

Application.  This  experiment  gives  a  very 
satisfactory  illustration  of  the  essential  changes 
which  may  be  produced  by  chemical  combination ; 
as  the  ammoniacal  gas  differs  so  widely  in  its 
properties  from  hydrogen  or  nitrogen. 

PRINCIPLE  3.     OF  LIME, 

Natural  Histonj  and  general  Remarks. 

Lime  is  very  abundant.  It  forms  the  basis  of 
all  lime  rocks  which  are  combined  with  carbonic 
acid,  whether  primitive,  transition  or  secondary  ; 
from  those  which  receive  a  polish  called  marble, 
to  the  roughest  of  the  common  lime  stone.  It  is 


140  CLASS   IV.      METALLOIDS. 

the  basis  of  chalk,  corol  rocks  and  shells.  Com- 
bined with  sulphuric  acid,  it  forms  the  vast  plas- 
ter beds  of  Nova- Scotia  and  our  western  districts. 
Combined  with  phosphoric  acid,  it  forms  the  bones 
of  animals. 

When  carbonate  of  lime  is  heated  about  as  high 
as  the  white  heat  of  iron,  the  carbonic  acid  is  con- 
verted into  a  gas  and  passes  oft*.  This  process  is 
conducted  in  large  kilns,  where  quicklime  is  man- 
ufactured. 

Prop.  1.  Pure  lime  has  a  strong  affinity  for 
water. 

Illustration.  Put  a  wine-glass  full  of  newly 
slacked  lime  into  a  quart  decanter,  and  fill  it  with 
water  After  shaking  it  about  a  minute,  let  it- 
stand  fifteen  or  twenty  hours  to  settle.  Now 
pour  oft'  the  colourless  liquid  into  large  vials  for 
use. 

Pour  some  of  the  lime  water  into  a  wine  glass 
and  test  it  by  a  few  drops  of  the  infusion  of  red 
cabbage.  It  will  become  green,  which  is  the  al- 
kaline test  ;  proving  that  the  water,  though  lim- 
pid, is  chemically  combined  with  lime. 

Application.  Stone  lime,  as  it  is  called,  dur- 
ing the  process  of  slacking,  attracts  water  so  pow- 
erfully as  to  convert  some  of  it  into  a  solid,  while 
other  portions  are  converted  into  vapour,  by  the 
caloric  disengaged  from  the  solidified  portion. 
The  same  slacked  lime  continues  to  attract  and  to 
solidify  water  for  a  long  time  when  in  the  state  of 
mortar.  It  is  said  that  mortar  grows  stronger  for 
centuries  by  the  slow  additions  of  water  and  car* 
feonic  acid. 

The  strong  affinity  of  quicklime  for  water  ren- 
ders it  an  excellent  drying  material..  Aa  enclosed 


PRINCIPLE    3.       OF    LIME.  141 

portion  of  atmospheric  air  or  of  any  other  gas  may 
be  dried  by  standing  over  unslacked  lime.  Col. 
Glbbs  greatly  improved  the  strength  of  gun-pow- 
der by  mixing  it  with  quicklime,  and  thereby  ef 
iectually  drying  it.  Vid.  Ainer.  Jour.  Science, 
vol.  I,  p.  87. 

Prop.  2.  Lime  water  strongly  absorbs  sulphu- 
retted hydrogen  gas,  and  forms  the  hydro-sulphu- 
ret of  lime. 

Illustration.  Pass  sulphuretted  hydrogen  gas 
into  lime  water,  as  directed  with  ammonia,  and 
the  hydro-sulphuret  will  be  formed. 

Application.  This  forms  a  good  test  for  met- 
als, but  not  so  delicate  as  the  hydro-sulphuret  of 
ammonia.  This  experiment,  showing  the  affinity 
of  lime  for  sulphuretted  hydrogen  gas,  demon- 
strates its  utility  in  cleansing  putrid  sinks,  &c. 
For  sulphuretted  hydrogen  being  the  essential 
part  of  most  of  the  nauseous  effluvia,  if  absorbed 
by  lime  the  most  disagreeable  nuisance  will  here- 
moved.  For  the  same  reason  lime  water  is  useful 
in  cleansing  offensive  ulcers,  &c. 

Prop.  3.  Most  salts  of  lime  have  a  strong  at- 
traction  for  water. 

Illustration.  The  salt  of  lime  called  gypsum, 
(sulphate  of  limcj  becomes  a  powerful  cement  by 
its  attraction  for  water,  after  its  native  portion  of 
water  has  been  disengaged  by  heat.  Pulverize  a 
portion  of  gypsum  and  heat  it  in  a  crucible,  cov- 
ered by  the  next  smaller  crucible  in  the  nest,  in- 
verted, until  it  is  to  a  white  heat.  Cork  it  close 
in  a  bottle  to  exclude  moisture.  Wet  up  a  portion 
of  this  powder  to  the  state  of  a  paste,,and  in  about 
five  minutes  it  will  become  solid.  Bricks,  stones. 
&c.  may  be  joined  by  it  very  firmly. 


142  CLASS    IV.      METALLOIDS. 

Application.  On  this  principle  a  cement  is 
made  in  a  large  way  for  busts,  for  the  manufacture 
of  buhr  millstones,  for  hard-finished  walls,  &c.  If 
it  hardens  too  quick,  a  weak  solution  of  animal 
glue  added  to  the  paste,  will  postpone  the  hard- 
ening. 

Prop.  4.  Lime  will  combine  with  carbonic  acids 
and  form  carbonate  of  lime. 

Illustration.  Set  a  tumbler  of  carbonic  acid 
gas  on  the  table,  covered  with  a  piece  of  paste- 
board. After  filling  a  low  small  glass  cup  with 
limpid  lime-water,  remove  the  pasteboard  and  let 
it  down  into  the  tumbler.  Now  stir  it  two  or  three 
minutes  with  a  rod,  and  it  will  absorb  so  much 
carbonic  acid  that  part  of  the  lime  will  be  carbon- 
ated, and  become  milky.  Now  take  out  the  cup 
and  set  it  by  a  few  minutes  to  settle.  On  careful- 
ly pouring  off  the  liquid,  fine  carbonate  of  lime, 
wh}cb  may  properly  be  called  fine  chalk,  will  be 
left.  This  may  be  tested  by  its  effervescing  on 
pouring  upon  it  a  little  diluted  sulphuric  acid. 

Application.  Thus  we  see  from  this  experi- 
ment, that  carbonic  acid  may  be  driven  from  lime- 
stone by  heat,  rendering  it  pure  quicklime  ;  and  it 
may  be  absorbed  from  the  atmosphere,  re-united, 
and  form  the  carbonate  again.  Thus  lime  mortar 
in  walls  becomes  solid  like  marble,  on  exposure 
to  air.  On  this  principle  a  bowl  of  lime-water  set 
in  a  room  and  occasionally  agitated,  would  absorb 
the  carbonic  acid  gas  when  a  large  quantity  had 
been  produced  by  the  breaths  of  a  crowd. 

Prop.  5.  Carbonate  of  lime  is  dissolved  in  car- 
bonated water,  and  will  be  deposited  ivhen  the  car 
Ionic  acid  is  abstracted. 


PRINCIPLE    3.      OF  LIME.  143 

Illustration.  Prepare  some  carbonate  of  lime 
as  directed  under  Prop.  4,  for  native  carbonate 
cannot  be  used  without  occupying  too  much  time 
for  a  lecture.  Drop  a  few  grains  into  a  florence 
flask  or  half-pint  matrass  or  bolthead,  half  filled 
with  carbonated  water.  It  will  give  a  cloudy  ap- 
pearance to  the  water  at  first ;  but  it  will  be  en- 
tirely dissolved  and  the  water  will  become  limpid 
again  in  a  few  seconds.  Now  set  the  flask  into  the 
lead  pot,  and  boil  the  water  four  or  five  minutes. 
Take  it  out,  wipe  it  clean  and  set  it  by  to  cool. 
After  it  is  cool  the  fine  carbonate  of  lime  will  ap- 
pear again  in  the  bottom  of  the  flask.  For  the 
carbonic  acid  being  driven  out  of  the  water  by 
heat;  the  carbonate  of  lime  is  deposited. 

Application.  This  experiment  explains  the 
manner  in  which  the  calcareous  tufa,  called  the 
high  rock  at  Saratoga,  is  formed,  and  numerous 
other  similar  deposites.  The  carbonate  of  lime 
is  brought  along  chemically  combined  with  the 
carbonated  water,  until  it  comes  out  to  be  exposed 
to  the  atmosphere.  Then  a  part  of  the  carbonic 
acid  escapes,  and  a  part  of  the  lime  is  deposited. 
Probably  the  numerous  deposites  of  this  mineral 
were  made  by  carbonated  waters  which  have  ceas- 
ed to  fUw  for  ages.  The  most  remarkable  local- 
ity within  my  knowledge,  is  at  the  head  of  Ots- 
quago  creek,  ten  miles  south  of  the  canal  at  Fort- 
Plain.  There  is  another  on  the  Erie  canal,  a  few 
miles  east  of  Salina. 

Remarks.  A  vacuum  almost  as  perfect  as  can 
be  obtained  by  the  air-pump,  may  be  produced  by 
lime-water  and  carbonic  acid  gas.  Fill  a  cologne 
bottle,  decanter,  bolthead,  or  other  suitable  ves- 
sel, with  carbonic  acid  gas.  Introduce  very  cold 


144  CLASS    IV.      METALLOIDS. 

well-prepared  lime  water  to  the  bottom  of  the  ves- 
sel through  a  tube,  sufficient  to  equal  one-eighth 
of  the  measure  of  the  gas.  It  must  be  introduced 
without  any  agitation.  Cork  the  vessel  perfectly 
tight.  Now  shake  it  violently.  The  lime  water 
will  absorb  the  gas  and  produce  a  vacuum.  If 
the  vessel  is  shaken,  the  water  will  strike  against 
the  sides  with  a  clinking  sound.  But  if  the  tem- 
perature of  the  water  is  raised  a  very  little,  it  will 
fill  the  vessel  with  vapour,  as  in  other  cases  when 
atmospheric  pressure  is  removed. 

Prop.  6.  Lime  has  a  strong  affinity  for  oily 
substances. 

•Illustration.  Pour  olive  oil  into  a  wine-glass  of 
lime  water,  and  the  white  liquid  soap  will  be  form- 
ed, by  the  union  of  the  oil  and  lime^  which  is  used 
as  a  remedy  for  burns. 

Application.  Lime  is  used  in  connection  with 
potash,  &c.  by  the  soap  boilers.  It  absorbs  oils 
feebly  in  the  state  of  a  carbonate.  The  leaves  of 
a  book  are  often  spotted  with  candle  grease,  lamp 
oil,  &c.  These  spots  may  be  totally  removed  by 
finely  pulverized  chalk  or  marble.  Let  the  leaf  of 
a  book  be  placed  between  two  pieces  of  white  pa- 
per, with  pulverized  chalk  interposed  on  both 
sides.  Then  set  a  common  smoothing  iron  upon 
it,  sufficiently  heated  to  melt  the  grease.  As  soon 
as  it  is  melted,  the  chalk  will  absorb  it. 

Prop.  7.  Lime,  when  mixed  with  silexoralu- 
mine,  renders  the  mixture  fusible. 

Illustration.  Put  a  little  potter's  clay  paste  into 
a  crucible,  and  heat  it  in  the  forge  as  high  as  the 
white  heat  of  iron.  Now  pour  it  out  upon  a  brick 
on  the  table,  and  the  class  will  see  that  it  is  not 


PRINCIPLE    3.       OF  LIME.  145 

melted.     Mix  some  of  the  same  kind  of  clay  inti- 
mately with  about  an  equal  quantity  of  pulverized 
marble  or  chalk,  and  heat  it  again  as  hot  as  be 
fore.    Pour  it  out,  and  the  whole  mass  will  spread 
upon  the  brick  in  the  state  of  melted  cinder. 

Application.  On  this  principle  potters  reject 
all  clay  which  contains  lime.  About  Albany  and 
other  places  along  the  banks  of  the  Hudson,  there 
is  an  abundance  of  the  finest  clay  ;  but  it  contains 
about  fifteen  per  cent  of  carbonate  of  lime.  This 
would  be  sufficient  to  cause  a  kiln  of  potter's  ware 
to  melt,  and  of  course  cannot  be  used.  The  car- 
bonate of  lime  can  always  be  detected  by  pouring 
on  a  few  drops  of  diluted  muriatic  acid.  Ever  so 
small  a  proportion  of  the  lime  will  cause  an  effer- 
vescence, and  prove  the  mass  to  be  clay-marl,  un- 
fit for  pottery. 

Prop.  8.  Lime  will  combine  with  muriatic  acid 
and  form  muriate  of  lime  ;  which  salt  in  solution 
will  change  to  solid  gypsum  on  adding  sulphuric 
acid. 

Illustration.  Pour  diluted  muriatic  acid  into  a 
tumbler,  consisting  of  about  three  times  as  much 
water  as  acid.  Drop  in  pulverized  chalk  or  mar 
ble  until  effervescence  ceases,  and  muriate  of  lime 
in  solution  will  be  formed.  Now  pour  a  spoonful 
into  a  wine-glass,  and  pour  into  it  sulphuric  acid  ; 
solid  gypsum,  sulphate  of  lime,  will  be  instantly 
formed  if  it  is  not  stirred. 

Application.  Most  of  the  hard  waters,  as  they 
are  called,  contain  muriate  of  lime  in  solution. 
From  this  experiment  it  appears,  that  muriate  of 
lime  may  be  decomposed,  and  other  salts  of  lime 
formed  which  are  insoluble.  Some  of  these  salts 

13 


146  CLASS    IV.      METALLOIDS. 

adhere  to  the  bottoms  and  sides  of  vessels,  as  tea 
kettles,  &c. 

Prop.  9.  Lime  will  combine  with  oxymuriatic 
acid  and  form  the  oxy  muriate  of  lime. 

Illustration.  Let  a  stream  of  oxymuriatic  acid 
pass  into  water,  in  which  finely  pulverized  and 
recently  slacked  lime  is  suspended  by  continual 
agitation.  In  the  large  way,  a  dry  powder  of 
newly  slacked  lime  is  agitated  in  a  strong  cask, 
and  the  gas  passed  into  the  cask,  which  is  absorb- 
ed by  the  lime.  Others,  however,  prefer  passing 
the  gas  into  hogsheads  of  water,  in  which  the  lime 
is  suspended  by  agitation.  For  an  experiment, 
it  ma^  be  pressed  from  a  bladder,  as  directed  in 
making  oxy muriate  of  potash.  But  the  bladder 
maj  he  held  in  the  hands  and  the  receiver  shaken 
continually. 

Application.  This  is  the  bleaching  salt,  now 
used  at  the  great  factories.  The  mariner  of  ap- 
plying the  salt  is  described  in  treatises  on  bleach- 
ing. It  would  be  too  long  an  article  to  introduce 
here.  Students  are  referred  to  the  factories. 

PRINCIPLE  4.     OF  BARYTES. 

Natural  History  and  general  Remarks. 

Barytes  possesses  many  properties  in  common 
with  lime.  It  is  found  in  the  United  States  in  the 
state  of  a  sulphate,  in  considerable  quantities. 
The  most  extensive  locality  perhaps  yet  discov- 
ered in  the  world,  is  that  in  Carlisle,  Schoharie 
county,  New- York.  This  is  a  fibrous  variety, 
but  differs  widely  in  its  external  characters  from 
the  fibrous  varieties  of  Europe.  It  is  called  Scho- 
harite,  from  its  local  situation,  being  near  the 


PRINCIPLE   4.       OF  SARYTES.  147 

western  bank  of  the  Schoharie  kill.  This  varie- 
ty is  an  excellent  flux  for  brazing,  &c.  Perhaps 
every  variety  is  equally  good  ;  hut  this  has  been 
proved  to  be  so  by  abundant  trials.  All  the  salts 
of  barytes,  excepting  the  sulphate,  are  most  dead- 
ly poi&ons. 

Prop.  I.  Carbonate  of  barytes  may  be  obtained 
from  the  native  sulphate,  by  exchanging  acids  with 
2)earlash,  the  sub-carbonate  of  potash. 

Illustration.  Put  into  a  gallipot  or  florence 
flask,  pulverized  sulphate  of  barytes  with  about 
three  times  as  much  pearlash,  and  apply  heat  .suf- 
ficient first  to  melt  the  pearlash  and  then  to  boil 
the  mixture  for  about  three  hours.  Water  may 
be  added  from  time  to  time.  Now  put  in  consid- 
erable water  so  as  to  make  a  very  diluted  solution. 
Let  it  stand  awhile,  and  the  carbonate  of  b  irytes, 
"which  is  produced  by  this  double  decomposition, 
•will  settle  to  the  bottom,  and  the  sulphate  of  pot- 
ash will  remain  in  solution.  Pour  off  the  liquid 
and  put  in  water  again,  and  thus  wash  it  two  or 
three  times,  and  it  will  be  ready  for  use. 

Application.  Having  obtained  carbonate  of 
barytes,  it  is  in  a  situation  to  be  readily  brought 
into  any  other  state.  As  it  has  a  stronger  affinity 
for  nitric,  muriatic  or  sulphuric  acid,  than  it  has 
for  the  carbonic,  either  of  those  salts  may  be  form- 
ed in  the  common  way.  Or  if  it  be  kept  at  a  white 
beat  in  a  crucible  about  half  an  hour,  the  pure  ba- 
rytes will  be  obtained.  This  will  combine  with 
water  like  lime,  and  form  the  barytic  water,  an 
excellent  test. 

Prop.  2.  Barytes  will  combine  with  muriatic 
or  nitric  acid,  and  form  a  test  for  the  presence  of 
sulphuric  acid. 


148  CLASS    IV.      METALLOIDS. 

Illustration.  Put  muriatic  or  nitric  acid  into 
a  tumbler  diluted  with  about  six  times  as  much 
water.  Drop  in  the  carbonate  of  barytes,  until 
effervescence  ceases. 

Application.  This  forms  a  perfect  tesf  for  sul- 
phuric acid  in  any  state  of  combination.  But  it  is 
a  most  deadly  poison. 

PRINCIPLE  5.     OF  STRONTIAN. 
Natural  History  and  general  Remarks. 

Strontian  has  lately  been  found  by  Professor 
Douglass  and  W.  A.  Bird,  in  great  abundance  on 
an  island  in  Lake  Erie,  in  the  state  of  a  sulphate. 
It  was  passed  from  hand  to  hand  among  mineralo- 
gists in  New- York  as  crystallized  sulphate  of  ba- 
rytes for  a  considerable  time.  I  first  analyzed  it 
before  the  members  of  the  Troy  Lyceum,  and  there 
demonstrated  it  to  be  sulphate  of  strontian.  I 
have  since  examined  its  geological  relations.  It 
is  found  only  in  a  kind  of  swine-stone  or  geodifer 
ous  limestone.  It  is  found  in  geodes  in* this  rock 
at  Rochester,  Lockport,  Niagara  Falls,  on  most 
of  the  islands  in  Lake  Erie,  &c. 

It  possesses  many  properties  in  common  with 
barytes,  and  its  salts  are  obtained  as  directed  un- 
der barytes  ;  but  none  of  its  salts  are  poisonous. 

Prop.  1.  The  salts  of  strontian  may  be  distin- 
guished from  those  of  barytes  by  the  colour  of  its 
flame  when  burned  with  alcohol. 

Illustration.  Dissolve  a  little  of  the  muriate  or 
nitrate  of  barytes  arid  of  strontian  in  separate  por- 
tions of  alcohol.  Drop  a  little  of  each  into  the 
burning  wicks  of  separate  candles,  The  barytic 


PRINCIPLE  6.      OF  MAGNESIA.  149 

salt  will  burn  with  a  yellow,  the  strontian  with  a 
deep  red,  flame.  The  solutions  may  be  held  in  the 
blaze  in  silver  tea-spoons,  and  they  will  burn  more 
elegantly. 

Application.  These  two  heavy  minerals  great- 
ly resemble  each  other.  They  are  both  used  for 
tests,  and  probably  may  both  be  useful  as  fluxes. 
They  will  both  combine  with  sulphuretted  hydro- 
gen, forming  hydro-sulphurets  ;  and  by  heating 
with  sulphur,  form  sulphurets  like  all  other  al- 
kalies, 

PRINCIPLE  6,     OF  MAGNESIA. 

Natural  History  and  general  Re?narks. 

Magnesia  forms  one  of  the  constituents  of  the 
soapstone  or  talcose  rocks,  of  asbestos,  and  some 
other  minerals.  It  is  found  pure,  or  merely  com- 
bined with  water,  in  connexion  with  soapstone 
and  serpentine  rocks,  at  Hoboken,  opposite  to 
New-York.  It  is  found  in  the  state  of  a  carbo- 
nate in  the  same  range  of  soapstone  or  talcose 
rock  on  Staten  Island.  It  is  found  in  the  state  of 
an  efflorescent  sulphate;,  (called  Epsom  salts)  in 
great  quantities  six  miles  north  of  Troy,  on  the 
east  bank  of  the  Hudson  ;  also  in  the  same  situa- 
tion at  Coeymans,  on  the  west  side  of  the  Hudson. 
Near  the  latter  place  is  a  spring  highly  charged 
with  it.  But  magnivsia  is  generally  obtained  from, 
sea- water,  after  it  is  separated  from  the  common 
salt.  It  exists  in  the  state  of  a  muriate  and  sul- 
phate in  sea- water,  from  which  it  is  obtained  by 
mixing  with  it  a  solution  of  common  pearlash.  A 
double  decomposition  takes  place  ;  and  while  the 
sulphate  of  potash  remains  in  solution,  the 

IB* 


150  CLASS   IV.      METALLOIDS* 

bonate  of  magnesia  falls  down.  The  carbonate 
of  magnesia  thus  obtained,  is  the  white  magnesia 
of  the  shops. 

Prop.  1.  The  carbonic  acid  may  be  driven 
from  its  connexion  with  the  magnesia  of  the  shops 
by  caloric. 

Illustration.  Drop  diluted  sulphuric  acid  upon 
carbonate  of  magnesia  of  the  shops  and  it  will  ef 
fervesce  violently  ;  that  is,  a  bubbling  will  be 
caused  by  the  escape  of  carbonic  acid  in  the  state 
of  gas.  Put  a  little  of  the  same  carbonate  of  mag- 
nesia into  a  crucible  and  keep  it  about  the  white 
heat  of  iron  fifteen  minutes.  Now,  after  it  cools, 
drop  on  it  diluted  sulphuric  acid  and  it  will  scarce- 
ly effervesce,  because  the  carbonic  acid  is  driven 
out.  If  a  little  of  it  be  dissolved  with  water  it 
will  give  the  alkaline  test  with  red  cabbage  much 
stronger  than  before  heating.  I  have  never  suc- 
ceeded in  driving  off  all  the  carbonic  acid  by  heat, 
so  that  no  effervescence  can  be  produced  by  the 
application  of  sulphuric  acid. 

Application.  This  is  called  the  calcined  mag- 
nesia ;  and  is  considered  as  a  more  efficient  reme- 
dy in  some  diseases  than  the  carbonate. 

Prop.  2.  Magnesia  will  combine  with  sulphur- 
ic acid  and  form  the  Epsom  salts. 

Illustration.  Put  sulphuric  acid  into  a  tum- 
bler, diluted  with  about  six  times  as  much  water. 
Drop  in  carbonate  of  magnesia  until  effervescence 
ceases.  This  will  form  Epsom  salts  in  solution. 
Pass  some  of  it  around,  and  the  class  will  recog- 
nize the  bitter  taste  of  the  Epsom  salts. 

Application.  This  salt  is  so  abundant  in  na- 
ture, that  it  is  never  prepared  in  this  way,  except 


PRINCIPLE    8.       OF  SILEX.  151 

ing  by  way  of  experiment,  or  when  a  practising 
physician  happens  to  be  in  want  of  this  article  of 
materia  medica. 

PRINCIPLE  7.     OF  LITHIA. 
Natural  History  and  general  Remarks. 

Lithia  is  an  alkali  found  in  a  rare  mineral,  call- 
ed petalite,  by  Arfvedson,  Berzelius'  assistant, 
in  the  proportion  of  5  or  6  per  cent,  with  about  79 
of  silex  and  16  of  alumine.  It  approaches  soda 
in  its  characters  ;  as  it  forms  a  salt  with  muriatic 
acid  resembling  common  salt  in  taste  and  in  its 
crystalline  form.  It  dissolves  very  slowly  in  wa- 
ter, giving  off  heat  like  lime  when  slacking.  It 
is  almost  as  caustic  to  the  taste  as  potash. 

SECTION  2.     EARTHS  WHICH   ARE    NOT    ALKA- 
LINE. 

General  Remarks. 

It  is  conjectured  from  analogy,  that  these  earths 
consist  of  peculiar  bases  united  to  oxygen.  These 
imaginary  bases  may  be  called  metalloids  also. 
Some  chemists,  however,  have  placed  silex  among 
oxidable  substances  not  metallic,  and  denominate 
it  silicon.  Gorham  has  followed  that  arrange- 
ment, but  Brande  has  not. 

PRINCIPLE  8.     OF  SILEX. 

Natural  History  and  general  Remarks, 

Silex  is  the  most  abundant  substance  known  te 
us.  It  constitutes  the  largest  proportion  of  most 


152  CLASS    IV*      METALLOIDS* 

rocks  and  soils.  No  rock  stratum,  excepting  some 
lime  rocks,  is  destitute  of  silex.  Quartz  crystals 
are  almost  pure  silex.  Most  gems,  excepting  the 
diamond,  the  pearl,  and  the  sapphire  family,  are 
chiefly  composed  of  silex.  The  common  gun-flint, 
the  carneliou,  and  the  quartz  crystal,  are  of  very 
common  use  in  the  arts. 

Prop.  1.  Silex  may  be  obtained  pure  from  its 
earthy  compounds,  by  combining  it  with  an  alkali 
and  then  separating  the  alkali  with  an  add. 

Illustration.  Previous  to  the  commencement  of 
the  lecture,  heat  a  gun-flint  red  hot  and  throw  it 
into  cold  water  in  order  to  render  it  brittle.  Pul- 
verize it  very  fine  and  mix  the  powder  with  about 
five  times  its  bulk  of  pearlash,  melt  the  mixture 
and  keep  it  in  the  state  of  fusion  fifteen  minutes. 
]SFow  dissolve  it  in  two  or  three  times  its  bulk  of 
water.  At  the  lecture  pour  in  diluted  sulphuric 
or  muriatic  acid,  a  little  at  a  time,  as  long  as  it 
continues  to  cause  a  precipitation.  After  it  stands 
a  little  while  to  settle,  pour  off  the  liquid  part,  and 
wash  or  rinse  the  precipitate  in  hot  water  several 
times  until  the  water  poured  off  is  tasteless.  This 
powder  is  pure  silex. 

Application.  This  substance  is  the  basis,  or 
rather  the  principal  ingredient  in  gun-flints,  rock 
crystal,  carnelion,  &c.  It  forms  much  the  larg- 
est proportion  of  soils  and  rocks.  It  is  soluble  in, 
fluoric  acid,  as  shewn  under  fluorine,  but  in  no 
other  acid.  Heat  rock  crystal  red  hot  and  plunge 
it  into  water,  and  then  pulverize  it,  and  it  will  be 
almost  pure  silex;  for  crystallized  quartz  consists 
almost  entirely  of  pure  silex  and  the  water  of  crys- 
tallization. 

From  the  experiment  described  under  tins  illus- 


PRINCIPLE  8.       OF  S1LEX.  153 

tration,  it  appears,  that  silex  is  readily  dissolved 
when  heated  with  potash.  On  this  principle  glass 
is  manufactured.  A  due  proportion  of  potash  and 
quartzose  sand  are  heated  together  and  fused  into 
liquid  glass.  This  substance  is  then  blown,  while 
it  adheres  to  the  end  of  a  tube,  into  the  various 
forms  required. 

Prop.  2.  Glass  sometimes  contains  the  oxid 
of  a  metal,  which  may  be  tarnished  by  hydro-sul- 
phuret  of  ammonia. 

Illustration.  Pour  some  hydro-sulphuret  of  am- 
monia into  any  vessel  of  flint  glass,  (which  always 
contains  red  lead)  and  it  will  become  dark  colour- 
ed and  cloudy  within,  after  standing  one  hour. 
At  the  same  time  pour  seme  into  a  vessel  of  crown 
glass,  bottle  glass,  or  on  common  window  glass, 
and  it  will  not  be  tarnished.  But  the  flint  glass 
vessel  ought  to  be  new  ;  for  if  it  has  been  used, 
the  lead  which  is  near  the  inner  surface  of  the  glass 
will  probably  be  worn  off  or  dissolved,  so  that 
none  will  be  left  to  receive  the  tarnish. 

Application.  False  gems  made  in  imitation  of 
true  ones  are  always  coloured  with  the  oxid  of  a 
metal.  Oxid  of  cobalt  colours  a  glass  gem  smalt 
blue — black  oxid  ,of  manganese,  violet — oxid  of 
chrome,  emerald  green,  &c.  If  any  such  imitation 
gem  be  put  into  the  hydro-sulphuret  of  ammonia, 
it  will  soon  become  tarnished. 

The  most  convenient  method  for  detecting  frauds 
of  artists,  practised  with  false  gems,  is  the  follow- 
ing :  Let  gems  be  divided  into  four  classes,  ac- 
cording to  their  hardness,  i.  Diamonds.  2.  The 
sapphire  class.  3.  The  rock  crystal  class.  4. 
Glass  imitation  gems.  When  a  gem  is  to  be  ex- 
aruinedj  look  out  a  smooth  face  upon  it  with  a 


154  CLASS    IV.       METALLOIDS. 

magnifying  glass.  Apply  to  that  face  a  point  or 
atigle  of  a  quartz  crystal  and  attempt  to  scratch  it. 
If  any  scratch  is  made,  attempt  to  scratch  the 
quartz  with  the  gem.  If  the  quartz  cannot  be 
scratched  by  it,  it  is  glass;  if  it  can,  it  is  quartz. 
Minerals  of  equal  hardness  will  scratch  each  oth- 
er; therefore  quartz  will  scratch  quartz,  &c.  If 
it  cannot  be  scratched  with  a  quartz  crystal,  it 
may  be  considered  as  belonging  either  to  the  sap- 
phire or  to  the  diamond  class.  In  this  class  are 
included  oriental  ruby,  oriental  amathyst,  oriental 
topaz,  corundurns,  emery,  &c.  Select  a  large 
smooth  grain  of  unground  emery,  and  apply  it  to 
the  face  of  the  gem  as  before  directed.  If  it  can  be 
scratched  with  emery,  but  with  great  difficulty, 
and  not  by  the  quartz  crystal,  it  may  be  consider- 
ed as  belonging  to  the  sapphire  class.  But  if  it 
cannot  possibly  be  scratched  with  emery,  after  the 
most  careful  trials,  with  severe  pressure,  it  is  a 
diamond. 

PRINCIPLE  9.     ALUMINE. 
Natural  History  and  general  Remarks. 

Alumine  is  the  most  generally  known  as  the  ba- 
sis of  clay;  though  common  clay  soil  contains 
more  silex  than  alumine.  It  constitutes  the  chief 
of  the  basis  of  alum.  It  is  a  constituent  of  every 
rock  stratum,  excepting  some  lime  rocks.  It  has 
been  found  in  a  pure  uncombined  state  in  but  one 
locality.  Dr.  E.  Emmons  discovered  it  in  the  sum- 
mer of  1819,  in  an  iron  mine  in  Richmond,  Mass. 
He  demonstrated  it  to  be  a  new  mineral  by  the 
Wernerian  external  characters,  without  a  chemi- 
cal analysis.  Professor  Dewey  was  the  first  who 


PRINCIPLE    9.      ALUMINE.  155 

proved  that  it  consisted  of  pure  alutnine  and  wa- 
ter. 

Clay  beds  are  generally  divided  into  the  marly 
clay  (according  to  Pierce,)  and  the  plastic  clay. 
The  clay-beds  of  the  United  States  are  chiefly  of 
the  marly  kind,  and  contain  from  ten  to  twenty 
per  cent  of  carbonate  of  lime.  These  beds  are  un- 
lit for  potter  bakers'  stone  ware  ;  because  such  a 
compound  fuses  before  it  is  sufficiently  baked. 
Plastic  ;  lay,  which  is  often  destitute  of  any  car- 
bonate of  lime,  is  of  great  value  in  the  arts.  It  is 
not  only  essential  to  the  potter  baker,  but  is  neces- 
sary for  the  construction  of  all  furnaces^  where  a 
high  heat  is  required. 

The  celebrated  Wedgewood's  ware  depends, 
for  its  peculiarity,  on  the  clay  being  burned  and 
pulverized  previous  to  its  final  manufacture. 

Prop.  1.  The  alum  of  commerce  consists  of 
alumine  combined  with  sulphuric  acid,  and  a  little 
potash  ;  from  this  salt  the  alumine  may  be  precip- 
itated by  ammonia. 

Illustration.  Dissolve  common  alum  in  water 
before  the  lecture  hour.  In  time  of  lecture,  pour 
into  it  liquid  ammonia  and  a  dense  precipitate  will 
appear.  ISow  let  it  settle  several  hours  and  pour 
off  the  liquid,  and  wash  this  precipitate  several 
times  in  water.  This  will  be  the  pure,  or  nearly 
pure,  alumine. 

Application.  This  is  the  basis  of  clay,  used  in 
the  laboratory  only. 

Prop.  2.  Alumine  mixed  with  silex,  forms  the 
chief  part  of  soils  ;  which  mixture  when  moisten- 
ed with  water,,  will  absorb  ammonia,  carbonic  acid 
gas,  carburetted  hydrogen  gas,  and  all  other  gases 
which  are  nutritious  to  growing  vegetables. 


156  CLASS   IV.      METALLOIDS. 

Illustration.  Prepare  opodeldoc  vials  of  these 
gases  over  mercury,  and  pass  into  them  separately 
balls  of  moistened  earth.  Some  portion  of  each 
gas  will  be  absorbed,  with  more  or  less  rapidity. 
Some  of  them  must  stand  several  hours. 

Application.  From  this  experiment  it  appears, 
that  the  more  frequently  the  moist  earth  is  present- 
ed to  the  atmosphere  by  frequent  hoeing,  harrow- 
ing or  ploughing,  the  more  of  the  nutritious  gases 
will  be  absorbed  from  it  This  absorption,  while 
it  enriches  the  soil,  purifies  the  air  and  renders  it 
better  fitted  for  respiration.  This  experiment  ex- 
plains the  cause  of  the  superior  fertility  of  soils  in 
the  vicinity  of  large  towns,  compared  with  similar 
soils  in  different  situations.  The  various  impuri- 
ties generated  in  large  towns,  the  vast  quantities 
of  carbonic  acid  gas  given  off  in  respiration,  the 
carburetied  hydrogen  and  carbonic  acid  gases 
from  a  multitude  of  chimnies,  &c.  so  highly  charge 
the  atmosphere  with  gases  which  are  favourable 
to  the  growth  of  vegetables,  that  the  very  winds 
become  the  fanners'  manure  carters. 

Prop.  3.  Acetate  ofalumine  is  made  by  double 
elective  affinity,  with  alum  and  sugar  of  lead. 

Illustration.  Dissolve  equal  parts  of  alum  and 
sugar  of  lead  in  water  in  separate  wine-glasses, 
before  lecture  hour.  At  the  lecture,  mix  these  so- 
lutions. The  acids  exchange  bases  ;  and  the  sul- 
phate of  lead  falls  down,  while  the  acetate  of  alu- 
inine  remains  over  it  in  a  liquid  state.  This  li- 
quid may  be  poured  off  for  use. 

Application.  Though  by  this  process  we  do 
not  obtain  a  perfectly  pure  salt,  Dr.  Cooper  says 
that  it  is  manufactured  in  this  way  by  the  calico 


PRINCIPLE    9.       OF  ALUMINE.  157 

printers.     It  is  an  important  mordant,  much  used 
in  dying. 

Prop.  4.  JLlumin&  attracts  water  powerfully, 
by  ichich  its  bulk  is  much  enlarged  ;  and  its  bulk 
becomes  greatly  diminished  by  forcing  out  the  wa- 
ter with  caloric. 

Illustration.  Make  small  clay  cakes  and  dry 
them  in  the  sun.  Now  bring  them  before  the 
class,  and  mark  their  dimensions  upon  a  board. 
Heat  them  in  a  crucible,  to  the  white  heat  of  iron. 
Cool  them  and  apply  them  to  the  measure,  and 
they  will  be  found  to  be  greatly  diminished  in 
size. 

Application.  On  this  principle  Wedgcwood 
constructed  his  pyrometer.  Nail  down  two  thirty 
inch  rulers  on  a  board,  half  an  inch  apart  at  one 
end  and  an  inch  apart  at  the  other.  Graduate  one 
of  the  rulers  with  marked  degrees.  If  the  sun 
dried  cakes  of  clay  would  just  enter  the  large  (Hid, 
after  heating  they  would  enter  considerable  far- 
ther. The  distance  to  which  they  would  enter 
would  indicate  the  degree  of  heat  which  had  been 
applied  to  the  crucible  containing  the  clay  cake 
and  the  metal,  or  other  substance  to  be  fused. 

On  this  principle  some  bricks  burned  at  a  kiln 
are  smaller  than  others,  though  all  were  made  in 
the  same  mould. 

Prop.  5.  JMumine  Jias  a  strong  affinity  for  tlie 
alkalies,  whether  they  are  simple  or  in  the  state  of 
salts, 

Illustration.  Lay  a  sun-dried  plastic  or  re- 
fractory clay  cake  obliquely  across  a  crucible,  of 
such  a  length  as  to  go  entirely  into  the  crucible, 
but  not  let  it  reach  the  bottom.  Heat  the  crucible 

14 


158  CLASS    IV.       METALLOIDS. 

until  the  clay  cake  is  at  a  white  heat.  Then 
throw  a  little  common  salt,  muriate  of  soda,  into 
the  crucible,  and  continue  to  raise  the  heat.  On 
taking  out  the  clay  cake  its  surface  will  be  found 
covered  with  a  glazing,  made  up  of  the  soda  and 
alumine  fused  together. 

Dip  a  dried  cake  into  mortar,  sufficiently  dilut- 
ed with  water  to  become  a  free  liquid,  which  is 
made  of  marly  clay.  Then  heat  it  as  before,  and 
it  will  become  glazed.  This  is  caused  by  the  fu- 
sion of  the  marly  clay  upon  the  surface  of  the  re- 
fractory clay  cake. 

Application.  The  affinity  between  lime  and 
alumine  has  an  useful  application  in  forming  plas- 
tering for  walls,  &c.  The  experiment  of  glazing 
the  clay  cake  is  an  exhibition  of  the  process  adopt- 
ed by  potter  bakers  for  glazing  their  ware,  by 
throwing  salt  into  the  kilns  when  the  ware  is 
burning. 

PRINCIPLE  10.     OF  GLYGINE. 
Natural  History  and  general  Remarks. 

Glycine  is  found  in  emerald  or  beryl.  The 
beryl  of  Haddam,  in  Connecticut,  yields  about 
fourteen  per  cent  of  glycine.  It  is  capable  of  be- 
coming a  slightly  adhesive  paste  in  water.  It  is 
dissolved  in  the  alkalies.  All  the  salts,  of  which 
it  forms  the  basis,  are  sweetish  and  somewhat  as- 
tringent. Not  used  in  the  arts. 

i 
PRINCIPLE  11.     OF  ZIRCON. 

Natural  History  and  general  RemarJcs. 
Zircon  is  found  in  granite  and  in  gneiss,  in  the 


PRINCIPLE   ?.      OF   THORINA,  159 

form  of  four-sided  prisms.  It  is  found  in  several 
localities  in  the  United  States.  The  crystals  con- 
tain about  twenty-five  to  thirty- live  per  cent  of  si- 
lex  and  a  little  oxid  of  iron.  The  pure  zircon  is 
insoluble  in  water,  but  unites  with  all  the  acids. 
Soluble  in  no  pure  alkali,  but  is  soluble  in  their 
carbonates.  Not  used  in  the  arts. 

PRINCIPLE  12.     OF  YTTRIA. 

Natural  History  and  general  Remarks. 

V7ttria  is  found  in  gadolinite  from  Sweden.  It 
is  combined  with  silex,  oxid  of  cerium  and  oxid 
of  iron.  When  pure  it  is  insoluble  in  water,  so- 
luble in  most  acids,  also  in  the  carbonate  of  am- 
monia. Some  chemists  consider  it  as  a  metal. 
It  is  a  doubtful  substance^  and  not  used  in  the 
.arts. 

PRINCIPLE  13.     OF  THORINA. 
Natural  History  and  general  Remarks. 

Thorina  was  lately  discovered  by  Berzelius,  in 
the  gadolinite  of  Sweden.  It  resembles  zircon. 
Its  salts  are  astringent  but  not  sweet.  It  is  ex- 
iremely  rare  and  not  used  in  the  arts. 


160 

CLASS  V.    METALS. 

General  Remarks. 

The  specific  gravity  of  all  pure  metals  is  above 
live.  They  all  reflect  light  brilliantly,  which  re- 
flection is  called  the  metallic  lustre.  Most  of  them 
are  found  in  the  earth  combined  with  oxygen  or 
sulphur.  All  are  capable  of  becoming  sulphurets 
by  heating  with  sulphur,  as  directed  in  preparing 
sulphuretted  hydrogen  gas.  Metals  may  be  com- 
bined or  alloyed  together,  in  which  state  their  fu 
sibility  is  increased. 

Many  experiments  upon  metals  require  so  much 
time  that  they  cannot  be  commenced  and  complet 
ed  in  the  course  of  a  lecture,  or  of  one  meeting  of 
the  class.     Others  are  of  a  difficult  or  rather  dan 
gerous  nature.     These  may  be  passed  over  in  a 
short  course  of  lectures,  after  giving  very  particu- 
lar explanations  of  their  principles  ;  and  shewing, 
as  well  as  can  be  done  conveniently  without  actu 
ally  performing  the   experiments,  the  necessary 
manipulations.     These  are  distinguished  by  au 
asterisk  (*)  prefixed  to  the  illustration. 

Prop.  1.  Ml  metals  must  be  in  the  state  of 
oxids  before  they  can  combine  with  acids  and  form 
salts. 

Illustration.  1.  Put  a  drop  of  mercury  into  a 
wine-glass  and  pour  muriatic  acid  upon  it.  Mu- 
riatic acid  cannot  be  decomposed  by  any  metal, 
and  mercury  cannot  decompose  the  water  which  is 
combined  with  the  muriatic  acid.  Consequently 
the  mercury  will  not  be  oxidated,  and  of  course 
cannot  become  the  base  of  a  salt  in  this  experi- 
ment. 


GENERAL    EXPERIMENTS.  161 

2.  Put  a  drop  of  mercury  into  a  wine-glass  and 
pour  nitric  acid  upon  it.      Though  the  water, 
which  is  combined  with  the  nitric  acid,  cannot  be 
decomposed  by  mercury,  nitric  acid  can.     Con- 
sequently the  mercury  will  be  oxidated  in  succes- 
sive atoms  by  successive  atoms  of  nitric  acid  : 
which   will  be  reduced  thereby  to  nitrous  acid, 
and  rise  up  in  a  deep  orange  gas,  as  described 
under  nitrogen.     As  fast  as  the  successive  atoms 
of  mercury  are  oxidated,  they  unite  with  the  near- 
est atoms  of  undecomposed  nitric  acid,  and  nitrate 
of  mercury  is  formed. 

3.  Pour  muriatic  acid  upon  nitrate  of  mercury, 
and  the  acid  will  take  up  the  base  of  the  nitrate ; 
because  the  mercury,   having  been  oxidated  by 
decomposing  the  nitric  acid,  readily  elects  the  mu- 
riatic acid,  for  which  it  has  the  stronger  affinity. 

4.  Put  a  small  quantity  of  iron  filings  into  a 
wine-glass,  and   pour  muriatic  acid   upon  it. — 
Though  the  muriatic  acid  cannot  be  decomposed 
by  the  iron  nor  by  any  other  metal,  as  before  ob- 
served ;  the  water  which  is  combined  with  the 
muriatic  acid  is  readily  decomposed  by  the  iron. 
That  the  iron  is  oxidated  by  the  oxygen  of  the 
water,  is  manifest  from  the  disengagement  of  hy- 
drogen gas  which   arises  out  of  the  wine-glass „ 
The  iron  being  thus  oxidated,  immediately  unites 
with  the  muriatic  acid  and  forms  muriate  of  iron. 

Hemark.  In  the  second  and  fourth  experiments 
considerable  effervescence  appears  in  the  wine- 
glass. In  the  second,  it  is  caused  by  the  escape 
•of  the  nitrous  acid  gas,  (or  rather  nitric  oxid  which 
becomes  nitrous  acid  when  it  comes  in  contact  with 
atmospheric  air,)  and  in  the  fourth  by  the  escape 
of  hydrogen,, 

14* 


162  CLASS   V.      METALS. 

Application.  Metals  may  be  thus  oxidated  by 
the  decomposition  of  acids  or  of  water,  or  they  may 
have  been  previously  oxidated  by  some  other  pro- 
cess. In  some  cases  a  metal  is  first  oxidated  by 
an  acid  which  it  can  decompose,  and  then  united 
to  a  different  one  by  double  decomposition.  For 
example,  in  preparing  muriate  of  mercury  of  tho 
shops,  the  mercury  is  first  combined  with  sulphu- 
ric acid,  because  it  will  decompose  that  acid  and 
become  oxidated.  Then  its  oxid  is  combined 
with  muriatic  acid,  by  heating  the  sulphate  of  mer- 
cury with  the  muriate  of  soda.  This  process  of 
double  decomposition  will  be  particularly  explain- 
ed under  mercury. 

Prop.  2.  Several  of  the  metals  may  be  burned 
with  a  brilliant  flame,  in  a  current  of  oxygen  gas. 

Illustration.  Make  a  hole  in  the  side  of  a  large 
piece  of  charcoal,  and  put  into  the  hole  some  iron 
filings,  iron  wire,  zinc  shavings,  lead  shavings, 
&c.  Having  filled  a  gas-holder  with  oxygen,  pro- 
vided with  a  tin  or  lead  tube,  terminating  in  a 
pipe-stem,  as  described  in  the  introduction  ;  hold 
the  charcoal  in  a  suitable  position  for  receiving 
the  current  of  oxygen  upon  the  metals.  Let  an 
assistant  hold  the  flame  of  a  candle  between  the 
inetals  and  the  pipe,  until  the  current  of  oxygen 
drives  the  flame  into  the  coal.  Then  remove  the 
candle  and  continue  the  current  of  oxygen,  en- 
larging or  contracting  it  at  pleasure  by  turning  the 
stop.  The  metals  will  burn  very  brilliantly,  each 
exhibiting  its  own  peculiar  flame. 

Application.  This  experiment  demonstrates 
the  combustibility  of  metals  ;  and  shows  the  ne- 
cessity of  adding  to  the  words  acidifiable  substan* 
ees  ia  the  title  of  the  third  class,  the  words  not  me* 


GENERAL   EXPERIMENTS.  16S 

tatlic.  For  all  combustible  substances  are  capa- 
ble of  uniting  with  oxygen,  and  do  unite  with  it 
during  the  process  of  combustion. 

Prop.  3.  JL  very  intense  heat  for  burning  met- 
als may  be  produced  by  a  current  of  oxygen  and 
hydrogen  gases  combined. 

Illustration.  Fit  the  ends  of  two  tobacco  pipe- 
stems  together  at  right  angles,  by  filing  them  with 
a  small  three  cornered  file  in  the  following  man- 
ner. File  the  hydrogen  pipe  flat  on  one  side  at 
the  end,  and  file  a  groove  across  the  end  at  right 
angles  with  the  flat  side.  File  the  oxygen  pipe  at 
the  end  so  as  to  make  a  shoulder  to  fit  against  the 
flat  side  of  the  hydrogen  pipe,  and  file  it  so  deep 
as  to  leave  but  half  of  the  hollow  of  the  pipe-stem  ; 
which,  when  the  pipes  are  put  together,  will  ex- 
actly coincide  with  the  groove  across  the  end  of 
the  hydrogen  pipe.  Now  bore  two  holes  in  a  slip 
of  a  pine  board,  in  a  direction  to  fit  in  the  pipes 
firmly,  with  their  ends  meeting  in  a  joint  at  right 
angles  as  before  described ;  but  they  ought  to  meet 
3  or  4  inches  from  the  board.  Fasten  the  board 
in  an  upright  position  to  support  the  pipes  steadi- 
ly. Having  filled  one  gas-  holder  with  oxygen  and 
another  with  hydrogen,  with  stop-cocks  fitted  m 
them  as  usual,  attach  two  leaden  tubes  to  the  stop- 
cocks at  one  end,  and  to  the  pipe-stems  at  the  oth* 
er,  so  as  to  conduct  the  proper  gas  to  its  respective 
pipe.  Now  turn  the  stop  of  the  hydrogen  gas- 
holder and  let  out  a  very  small  stream  and  inflame 
it  with  a  candle.  Then  turn  the  stop  of  the  oxy- 
gen gas-holder,  and  let  out  a  stream  of  oxygen 
rather  larger  than  that  of  the  hydrogen.  A  small 
faint  blaze  will  be  produced,  but  its  heat  will  be 
very  intense.  Having  previously  providedi  the 


164  CLASS   V.      METALS. 

different  metals  intended  to  be  burned,  now  apply 
them.  Small  rods  of  iron,  lead,  copper,  &c.  and 
gold  and  silver  leaf,  will  burn  like  tinder.  A  very 
thin  file  with  a  long  wooden  handle,  will  burn 
beautifully. 

Application.  On  this  principle  minerals  can  be 
burned  or  fused  which  resist  the  strongest  furnace 
heat. — This  is  called  the  oxi-hydrogen  blow-pipe 
of  Hare  &  Silliman. 

Prop.  4.  Metals,  when  cold  as  it  is  possible  to 
make  them,  give  off  calorie  if  their  particles  art 
made  to  approach  each  other. 

Illustration.  Anneal  a  common  nail- rod,  and 
when  cold,  hammer  a  small  portion  of  it  very 
briskly  upon  an  anvil,  and  it  will  become  hot — if 
continued  until  it  is  drawn  out  very  small,  it  will 
become  red  hot.  The  stme  rod,  or  a  large  anneal- 
ed wire,  will  become  hot  by  frequent  bending  back 
and  forward. 

Application.  A  fire  may  be  kindled  by  violent- 
ly compressing  a  metal,  while  in  contact  with  any 
highly  combustible  substance. 

Prop.  5.  Letters  may  be  etched  upon  metals  by 
converting  the  surface,  ivhere  the  strokes  are  to  be 
etched,  or  the  interstices  betiveen  them,  into  oxids, 
or  salts. 

Illustration.  Dip  a  clean  copper  cent  into  melt 
ed  white  wax.  On  taking  it  out  the  wax  will  im- 
mediately harden  upon  it.  Mark  out  the  form  of 
a  letter  or  figure  upon  it.  Then  immerse  the  cent 
in  the  nitric  acid,  and  let  it  remain  fifteen  minutes. 
Now  take  it  out,  scrape  off  the  wax,  and  wash  the 
\vhole  clean.  The  letter  will  be  etched  upon  the 
cent. 


GENERAL   EXPERIMENTS.  165 

Application.  On  this  principle  the  etching  up- 
on razors,  sword  blades,  &c.  is  performed.  But 
the  artists  have  various  methods  for  preparing  com- 
positions for  applying  to  the  metals  before  the  acid 
is  applied.  They  generally  make  use  of  some- 
thing for  writing  the  letters,  which  will  flow  from 
the  pen  like  ink.  Then  they  surround  the  whole 
space  to  be  acted  upon,  by  an  edging  to  confine  the 
acid,  and  pour  on  the,  acid  instead  of  immersing 
the  metal  in  it.  This  is  called  etching  in  basso- 
relievo. 

Prop.  6.  Metallic  salts  maybe  decomposed  very 
readily  by  alkalies  and  alkaline  salts,  unless  the 
acid  is  metallic.  ~ 

Illustration.  Dissolve  in  separate  wine-glasses 
a  little  copperas,  blue  vitriol,  white  vitriol,  and  su- 
gar of  lead.  Pour  into  each  a  small  quantity  of 
the  solution  of  either  potash,  soda,  or  ammonia., 
and  the  metallic  oxid  of  the  salt  will  be  precipit- 
ated, and  an  alkaline  salt  formed  in  each  glass. 
But  if  chromate  of  potash  be  dissolved,  and  sugar 
of  lead  in  solution  be  poured  into  it,  chromate  of 
lead  will  be  produced.  For  the  acid,  being  me- 
tallic, has  the  strongest  affinity  for  metallic  oxidso 

Application.  This  principle  is  of  much  use  in 
the  manufacture  of  articles  used  in  medicine  and 
the  arts,  as  will  appear  by  attending  to  the  daily 
business  of  every  laboratory. 

SECTION  1.  METALS  WHICH  ABSORB  OXYGEN 
WITH  SUCH  FORCE  AS  TO  DECOMPOSE  WATER^ 
WHEN  HEATED  TO  REDNESS. 

Illustration.  The  distinctive  character  of  this 
section  may  be  illustrated  by  heating  an  iron  roc 
to  a  high  red  heat  arid  plunging  it  into  a  narrow 


166  "    CLASS    V.       METALS. 

mouthed  tin  cup  of  water.  The  smell  of  hydro- 
gen will  immediately  be  perceptible  at  the  mouth 
of  the  cu;;,  proving  the  decomposition  of  water; 
and  on  taking  out  the  rod  it  will  be  covered  with 
scales  of  protoxid  of  iron. 

PRINCIPLE  1.     IRON. 

Natural  History  and  general  Remarks. 

Iron  is  distinguished  in  the  arts  by  three  gener- 
al kinds  :  Cast  iron,  wrought  iron  and  steel.  Cast 
iron  contains  a  proportion  of  carbon,  and  is  of  a 
brittle  granulated  structure.  By  melting  cast  iron 
and  stirring  it  while  in  fusion,  part  of  the  carbon 
is  burned  out.  Then  by  hammering  or  rolling,  il 
becomes  almost  pure,  fibrous  and  tough,  and  is  then 
called  wrought  iron.  After  it  is  brought  to  the 
state  of  wrought  iron,  it  may  be  converted  into  steel 
by  heating  in  a  confined  place  in  contact  with  char- 
coal, with  which  it  combines.  It  will  then  become 
hard  on  heating  and  plunging  into  cold  water,  and 
is  more  fusible. 

Besides  the  cast  iron  and  steel,  iron  enters  into 
another  state  of  combination  with  carbon,  forming 
the  plumbago  or  black  lead,  as  it  is  called.  This 
is  considered  as  the  true  carburet  of  iron,  consist- 
ing of  95  per  cent  of  carbon  with  5  of  iron,  accord* 
ing  to  Allen  and  Pepys. 

Oxids  of  iron  form  the  basis  of  most  colours  in 
minerals  and  vegetables.  Gorham  quotes  from 
Hauy  this  elegant  and  appropriate  expression — 
(( when  nature  takes  the  pencil,  iron  is  the  colour- 
ing she  always  uses." 

Iron  is  rarely  found  pure.  It  is  most  generally 
found  in  the  state  of  an  oxid  or  of  a  sulphuret : 
though  it  is  found  in  the  state  of  a  carbonate,  sul- 


PRINCIPLE    1.      IRON,  167 

phate,  phosphate,  arseniate,  chromate,  muriate, 
&c.  In  the  oldest  primitive  rocks  it  is  generally 
found  in  the  state  of  a  protoxid,  and  is  consider- 
ably magnetic.  In  secondary  rocks  and  in  allu- 
vial deposites,  it  is  often  founti  in  the  state  of  a  pe~ 
roxid,  and  compounded  with  clay :  It  is  then 
called  argillaceous  iron  ore.  In  the  more  recent 
primitive  formations,  it  is  found  in  a  mixed  state, 
consisting  of  the  protoxid  and  peroxid,  in  various 
proportions.  It  is  then  called  hematitic  oxid  of 
iron. 

Iron  is  the  most  abundant  and  the  most  useful  of 
all  the  metals. 

Prop.  1.  Steel  may  be  distinguished  from  iron 
by  the  action  of  an  acid  upon  its  carbon. 

Illustration.  Let  fall  one  drop  of  nitric  acid 
upon  a  piece  of  polished  iron,  and  another  upon  a 
piece  of  polished  steel.  The  acid  on  the  iron  will 
be  limpid  or  whitish,  that  on  the  steel  will  become 
dark  brown  or  black. 

Application.  It  is  often  very  convenient  to  have 
a  more  ready  method  for  distinguishing  between 
iron  and  steel  than  the  usual  method  of  trying  its 
hardening  quality.  It  is  not  necessary  to  polish 
the  iron  or  steel  to  make  the  trial.  If  a  small  spot 
on  a  coarse  bar  of  iron  or  steel  be  filed  bright  it 
will  be  sufficient. 

Prop.  2.  Iron  becomes  oxidated,  on  exposure 
to  air  and  water;  and  the  red  oxid,  or  iron  rusty 
thus  made,  always  contains  some  carbonate  of  iron 
in  combination. 

Illustration.  Collect  some  red  iron  rust  and 
pour  muriatic  acid  upon  it,  and  carbonic  acid  will 
escape.  Or  heat  it  in  a  gun-barrel,  as  in  obtain- 


168  CLASS    V.      METALS. 

ing  oxygen  from  manganese,  and  carbonic  acid 
may  be  collected. 

Application.  Iron  rust,  prepared  by  exposing 
very  fine  iron  filings  to  water  and  air,  is  often  used 
in  medicine  as  a  tonic.  But  it  is  a  mistake  to  call 
this  oxid  of  iron  ;  as  it  is  a  mixture  of  oxid  of  iron 
and  carbonate  of  iron. 

Prop.  3.     Pure  red  oxid  of  iron  may  be  obtain- 
ed by  driving  out,  with  caloric,  the  reduced  acid 
from  a  salt  of  iron. 

Illustration.  Put  some  copperas,  sulphate  of 
iron,  into  an  unglazed  crucible,  and  heat  it  moder- 
ately until  it  becomes  a  dry  white  mass.  Then 
put  it  into  a  crucible  which  will  bear  a  high  heat, 
and  raise  the  heat  until  it  becomes  very  red. 
Though  copperas  consists  of  the  protoxid  of  iron 
and  sulphuric  acid,  we  obtain  the  peroxid.  For 
a  part  of  the  sulphuric  acid  is  decomposed,  and 
thereby  furnishes  an  other  proportion  of  oxygen  to 
the  iron. 

Application.  Here  the  iron  is  left  in  the  state 
of  a  peroxid,  after  the  sulphuric  acid  is  driven  oft* 
in  the  state  of  gas.  Sulphuric  acid  was  at  first  ob- 
tained by  heating  copperas  in  earthen  retorts,  and 
bringing  over  most  of  the  acid.  Copperas  being 
called  green  vitriol,  this  acid  was  called  vitriolic 
acid;  and  by  some,  the  oil  of  vitriol,  on  account 
of  its  flowing  like  oil. 

Prop.  4.  Sulphate  of  iron,  (copperas,)  is  form- 
ed by  the  chemical  combination  of  iron  and  sulphur- 
ic acid. 

Illustration.  Put  dilated  sulphuric  acid  into  a 
florence  flask,  consisting  of  about  five  times  as 
much  water  as  acid.  Apply  a  very  little  heat,  so 


PRINCIPLE    1.      IHOX. 

as  rather  to  warm  than  heat  the  acid.     Drop  in 
iron  filings  until  they  will  fall  to  the  bottom  quiet 
ly.    Pour  off  the  clear  liquid  into  earthen  plates. 
This  is  copperas  in  solution  ;  and  by  a  slow  eva- 
poration it  may  be  crystallized. 

Application.  On  this  principle  the  copperas  of 
commerce  is  manufactured  ;  but  the  process  is  ve- 
ry different.  Iron  pyrites  is  moistened  and  ex- 
posed to  the  atmosphere  a  considerable  time  in  a 
shallow  vat  or  box.  After  it  becomes  covered 
with  a  crust  it  is  dissolved  in  wafer,  or  leached, 
and  evaporated.  There  is  an  extensive  rnanufac 
tory  in  Vermont;  and  a  profitable  one  might  be 
established  on  the  east  face  of  the  Helderberg,  14 
miles  from  Albany. 

Prop.  5.  Iron  will  combine  directly  with  sul* 
phur  %  the  agency  of  caloric,  and  form  sulphuret 
of  iron. 

Illustration.  Perform  this  experiment  as  di 
rected  in  preparing  sulphuretted  hydrogen  gas. 
Or  heat  the  end  of  a  bar  of  iron  almost  to  a  white 
heat.  Apply  the  hot  end  to  a  common  roll  of 
brimstone.  The  iron  and  sulphur  will  unite  and 
form  iron  pyrites.  A  small  roll  of  brimstone  has 
been  made  to  perforate  a  large  bar  of  iron,  ivhcn 
highly  heated. 

Application.  Vast  quantities  of  -sulphuret  of 
iron  are  found  in  the  earth  ;  but  *«ese  substances 
seem  to  be  more  perfectly  united  than  they  can  be 
by  art.  The  native  sulpbaret  is  rarely  used  for 
composing  sulphuretted  Hydrogen. 

Sulphur  and  iron,  *v'hen  in  combination,  seem 
to  be  strongly  predisposed  to  combine  with  oxy- 
gen. On  this  principle  the  oxygen  is  taken  from 
an  enclosed  portion  of  atmospheric  air,  as  direct- 

15 


170  CLASS    V.      METALS. 

ed  under  nitrogen.  Lemery  produced  artificial 
volcanoes,  by  ramming  with  force  into  a  large  pot, 
a  paste,  made  of  100  Ib.  of  iron  filings,  intimately 
mixed  with  100  Ib.  of  pulverized  sulphur,  and  just 
water  enough  to  make  a  dense  paste.  This  pot  is 
then  buried  to  a  considerable  depth  in  the  earth, 
and  between  ten  and  twenty  hours  afterwards,  it 
bursts  out  and  burns  with  great  force.  I  do  not 
know  that  tHs  experiment  was  ever  repeated  in 
America.  L  is  said  that  no  effect  can  be  produc- 
ed without  a  xery  large  quantity  of  the  mixture. 

Though  iron  is  mineralized  with  sulphur,  oxy- 
gen and  carbonic  acid,  it  does  not  enter  into  many 
alloys.  The  principal  alloy  of  iron  known  in  the 
arts,  is  that  of  the  sheet  tin. 

PRINCIPLE  2.     MANGANESE. 
Natural  History  and  general  Remarks. 

Manganese  is  found  in  the  state  of  a  peroxid  at 
various  intervals  along  the  west  side  of  the  Green 
Mountain  range  from  Canada  to  the  southwest 
corner  of  Massachusetts.  It  often  accompanies 
the  hematitic  iron  ore.  It  is  generally  found  in 
the  most  recent  primitive  rocks,  or  in  alluvial  de- 
posites  consisting  of  these  rocks,  in  a  state  of  dis- 
integration. In  small  quantities  it  is  very  exten- 
sively diffused  in  both  continents  ;  and  is  often 
found  in  quantities  sufficient  for  workinr.  No 
preparation  is  retired  ;  it  is  merely  dug  from  the 
earth  and  sent  to  thb  bleachers.  It  is  extremely 
difficult  to  reduce  it  to  tije  pure  metallic  state. 

Prop.  1.  The  peroxid  of  manganese  (usually 
called  the  black  oxid)  readily  gives  off  its  highest 
portion  of  oxygen  on  being  subjected  to  the  red 
neat  of  iron. 


PRINCIPLE  3.      TIN. 

Illustration.  Produce  oxygen  from  it  as  direct- 
ed under  oxygen. 

Application.  On  this  principle  the  manganese? 
as  found  in  Trainer's  mines  at  Bennington,  Da- 
vey's  mine  near  Whitehall,  and  other  places,  is 
very  useful  for  converting  muriatic  acid  into  chlo- 
rine for  making  the  bleaching  liquor,  as  explained 
under  chlorine. 

Prop.  2.  The  yeroxid  of  manganese  is  reduced 
to  the  protoxid9  and  oxygen  given  off,  by  the  appli- 
cation of  an  acid  which  combines  with  the  protoxid 
only. 

Illustration.  Pulverize  some  manganese  very 
finely,  and  put  it  into  a  retort.  Pour  on  it  just 
enough  strong  sulphuric  acid  to  moisten  it,  or 
to  wet  it  moderately.  Set  the  retort  into  the  lead 
pot,  and  raise  the  heat,  but  not  to  a  degree  by  any 
means  sufficient  to  drive  out  the  oxygen  in  the 
usual  way,  and  oxygen  gas  will  soon  come  over. 

In  this  experiment  the  sulphuric  acid,  on  being 
heated  in  contact  with  the  manganese,  combines 
with  the  protoxid,  forming  sulphate  of  manga- 
nese, and  presses  out  the  oxygen  above  that  pro- 
portion. 

Application.  On  this  principle  oxygen  is  fur- 
nished to  the  muriatic  acid  in  the  production  of 
chlorine,  as  described  under  chlorine,  at  the  in- 
stant of  its  disengagement  from  the  soda  of  the  ta- 
ble salt. 

PRINCIPLE  3.     TIN. 
Natural  History  and  general  Remarks. 

Tin  has  not  yet  been  found  on  the  continent  of 
America,  excepting  a  small  quantity  in  Mexico, 


***  CLASS   V.       METALS. 

The  most  extensive  mine  is  that  of  Cornwall,  in 
England.  It  is  found  in  small  quantities  (always 
in  granite  or  gneiss)  in  Spain,  France,  Ireland, 
Sweden,  Bohemia,  Saxony  and  the  East  Indies. 
It  is  mostly  in  the  state  of  an  oxid. 

The  tin  foil  is  pretty  pure,  and  the  grain  tin 
considerably  so.     What  is  called  block  tin  was 
chiefly  tin  half  a  century  ago.     Now  it  is  gener 
ally  much  alloyed  with  lead. 

Tin  alloyed  with  lead  forms  pewter.  But  it  is 
most  extensively  used  for  covering  the  surface  of 
thin  sheets  of  iron,  called  sheet  tin.  When  tin  is 
thus  applied  in  a  pure  state,  it  forms  very  useful 
ware.  But  the  high  price  of  tin  encourages  manu- 
facturers to  alloy  the  tin  with  lead  and  thus  injure 
the  ware. 

Prop.  i.  Tin  is  not  oxidated  at  the  common 
temperature. 

Illustration.  Wet  a  piece  of  tin  foil  and  a  case 
knife  blade,  and  put  them  by,  under  the  cistern  or 
elsewhere,  in  a  damp  place.  The  next  day  show 
them  to  the  class — the  knife  blade  will  be  covered 
with  rust,  (or  oxid  of  iron  and  carbonate  of  iron) 
but  the  surface  of  the  tin  will  not  be  affected  by 
oxygen. 

Application.  On  account  of  this  property  of 
tin,  iron  plates  are  covered  with  tin,  forming  the 
tin-plate  ware.  Lightning  rods  are  tipped  with 
tin  to  prevent  the  points  from  rusting.  Copper 
vessels  are  tinned  inside  for  the  same  reason. 

Prop.  2.  Tin  is  oxidated,  when  heated  so  as 
to  be  brought  to  the  state  of  fusion. 

Illustration.  Put  some  tin  in  an  iron  ladle,  and 
Iieat  it  no  higher  than  merely  to  melt  it.  The 


PRINCIPLE    3.      TIN.  173 

surface  will  immediately  absorb  oxygen  from  the 
atmosphere  sufficient  to  form  the  protoxid  of  tin, 
called  the  yellow  oxid.  This  may  be  scraped  off 
with  an  iron  poker,  when  another  similar  pellicle 
will  be  formed  ;  and  the  succession  may  be  con- 
tinued until  the  whole  mass  is  a  yellow  oxid. 

If  the  protoxid  of  tin  is  put  into  a  crucible,, 
heated  to  redness,  and  continually  stirred  with  an 
iron  rod  for  some  time,  it  will  absorb  another  defi- 
nite proportion  of  oxygen.  It  then  becomes  the 
peroxid  of  tin,  called  the  white  oxid,  or  putty  of 
tin. 

Application.  The  white  oxid  of  tin  is  an  ex- 
cellent powder  for  sharpening  edge  tools,  as 
knives,  razors,  &c.  Also  for  polishing  burnish- 
ers' glass  tenses,  &c.  When  this  oxid  is  melted 
with  glass  it  forms  the  white  enamel  used  for  clock 
and  watch  faces,  &c. 

Prop.  3.  Tin  combines  with  mercury  at  the 
common  temperature  ;  and  at  the  time  of  its  amal- 
gamation with  mercury  will  adhere  to  glass. 

Illustration.  Put  a  drop  of  mercury  into  a  wine 
glass,  and  drop  into  it  small  pieces  of  tin  foil, 
which  will  become  liquified  and  unite  with  the 
mercury.  Continue  these  additions  until  the  amal- 

fim  contains  about  half  as  much  tin  as  mercury, 
ext  spread  a  small  piece  of  tin  foil  very  evenly 
on  the  face  of  a  smoothing  iron  or  a  piece  of  pol- 
ished marble.  Pour  the  amalgam  upon  k  and  rub 
it  over  the  tin  foil  with  the  finger  for  about  two 
minutes.  Now  press-  upon  it  a  piece  of  dry  clean 
glass.  Press  it  down  with  such  fcrce  as  to  press 
out  all  the  uncombined  mercury.  Lay  a  weight 
the  glass  and  leave  it  half  an  hour  5 

is* 


174  CLASS   V.      METALS. 

• 

it  may  be  taken  up,  and  will  be  found  to  be  a 
mirror. 

Application.  All  looking  glasses  are  made  in 
this  way.  lA  the  large  way  a  marble  slab  is  plac- 
ed in  an  inclined  position,  so  that  the  excess  of 
mercury  runs  off  and  is  saved  for  the  next,  &c. 

Prop.  4.  Tin  will  form  an  imperfect  alloy 
with  iron. 

Illustration.  Prepare  a  very  thin  slip  of  iron 
and  scour  it  bright,  dipping  it  several  times,  while 
scouring  it,  in  very  dilute  sulphuric  acid.  Bend 
one  end  of  it,  so  that  it  will  fit  the  inside  of  the 
bottom  of  a  crucible.  Melt  some  tin  in  the  cruci- 
ble, and  dip  the  bent  end  of  the  slip  of  iron  into  it. 
The  tin  will  combine  with  the  surface  of  the  iron, 
and,  if  it  is  very  thin,  it  will  penetrate  entirely 
through  it. 

Application.  On  this  principle  the  sheet  tin  is 
manufactured.  We  may  often  find  sheets  of  tin, 
which,  on  cutting  them  across,  appear  to  be  al- 
loyed entirely  through  with  the  tin  ;  and  may  be 
soldered  after  considerable  is  worn  from  the  sur- 
face. 

Prop.  5.  Tin  will  adhere  to  the  surface  of  cop  ^ 
yer,  if  perfectly  cleaned  and  heated. 

Illustration.  Prepare  a  slip  of  copper  by  scrap  • 
ing  it  well  with  a  knife  and  rubbing  it  over  with 
sal  ammoniac,  (muriate  of  ammonia.)  Now  heat 
the  copper  over  clean  coals,  which  do  not  «mit 
smoke ;  at  the  same  time  rubbing  it  over  with  ros- 
in. While  hot,  and  thus  cleaned  with  the  sal  am- 
moniac and  rosin,  rub  tin  upon  it  in  the  solid  state, 
which,  being  melted  by  the  heat  of  the  copper  will 
Adhere  to  it,  giving  it  a  silvery  white  surface. 


PRINCIPLE  4.    ZINC:.  175 

Application.  By  a  similar  process  copper  ket- 
tles and  other  copper  vessels  are  tinned  inside. 
When  the  tin  has  worn  off,  any  ingenious  house- 
keeper jaight  repair  it  in  this  way. 

Prop.  6.  Tin  dissolved  in  nitr^-muriatic  acid 
(aqua  regia)  forms  the  muriate  of  tin  ;  used  for 
giving  cochineal  the  scarlet  colour, 

Illustration.  Prepare  the  nitro-muriatic  acid 
by  mixing  one  part  of  muriatic  acid  with  two  of 
nitric  acid,  and  put  a  very  small  quantity  into  a 
florence  flask.  Drop  tin  into  it  by  small  quanti- 
ties, that  it  may  not  become  too  hot  by  the  rapid 
union  of  the  tin  and  acid.  After  the  acid  is  satu- 
rated, dissolve  some  of  it  in  water. 

Application.  Dissolve  in  water  in  a  wine-glass 
a  single  cochineal  insect  of  the  shops,  and  drop  in 
a  little  muriate  of  tin  ;  and  it  will  become  of  a 
bright  scarlet. 

It  may  be  made  by  dissolving  the  tin  in  strong 
muriatic  acid,  and  then  exposing  it  some  time  to 
the  atmosphere.  When  muriatic  acid  is  used,  the 
tin  takes  the  lowest  portion  of  oxygen.  It  is  then 
the  proto-muriate  of  tin.  When  the  nitro-murj- 
atic  acid  is  used,  the  tin  takes  the  highest  portion 
of  oxygen.  It  is  then  the  per-muriate  of  tin. 
But  if  the  proto-muriate  of  tin  is  exposed  to  the 
atmospheric  air,  the  tin  takes  another  portion  of 
oxygen,  becoming  the  peroxid;  and  the  salt  is  of 
course  the  per-muriate  of  tin,  which  is  used  by 
dyers. 

PRINCIPLE  4.     ZINC. 
Natural  History  and  general  MemarJcs. 
Zinc  is  mostly  found  in  the  state  of  a  sulphuret. 
It  accompanies  lead  in  most  mines.  It  is  found  in 


176  CLASS   V.      METALS. 

the  Southampton  lead  mines  in  granite  and  gneiss. 
It  is  found  in  crystals  of  a  waxy  hue  and  almost 
transparent  in  the  geodiferous  lime  rock  (or  swine- 
stone)  every  where  from  Genesee  river  to  20  or  30 
miles  west  of  Niagara  falls. 

Alloyed  with  copper  it  forms  brass.  It  has  a 
strong  attraction  for  oxygen — by  the  aid  of  sul- 
phuric acid,  it  rapidly  decomposes  water.  On 
account  of  its  strong  attraction  for  oxygen,  it  is 
used  for  the  positive  sides  of  the  pairs  of  metallic 
plates  in  a  galvanic  battery. 

Prop.  i.  Zinc  forms  a  white  oxid,  very  light 
andflocculent,  on  being  melted  and  lolled  in  con- 
tact with  atmospheric  air. 

Illustration.  Put  into  a  crucible  one  ounce  of 
zinc.  Raise  the  heat  so  as  to  melt  it,  and  then 
boil  it  a  short  time.  Now  raise  the  heat  still  high- 
er and  stir  it  with  a  rod.  Flocculent  flakes  of 
the  white  oxid  will  begin  to  fly  out  of  the  crucible. 
Take  the  crucible  out  of  the  fire  and  hold  it  in  fair 
view  of  the  class,  continually  stirring  it.  The 
room  will  now  be  filled  with  the  oxid,  which  is 
carried  about  by  the  air  like  fine  down. 

Application.  This  is  the  substance  which  was 
formerly  called  white  nothing,  (nihi.1  album,)  phi- 
losopher's wool  and  pompholiw.  In  medicine  it 
was  called  flowers  of  zinc.  When  intended  for 
medical  use  it  is  collected  from  the  sides  of  the 
crucible,  put  into  water,  and  stirred  up  awhile ; 
then  suffered  to  settle.  Afterwards  the  water  is 
poured  offend  the  oxid  is  dried  and  put  up  for 
use. 

Fine  filings  of  zinc  may  be  oxidated  and  inflam- 
ed with  explosion,  by  mixing  it  with  oxymuriate 
of  potash  and  striking  the  mixture  with  a  hammer 
ou  an  anvil, 


PRINCIPLE    5.       CADMIUM.  177 

Prop.  2.  Kinc  combines  with  sulphuric  acid 
and  form*  sulphate  oj  zinc,  called  white  vitriol. 

Illustration.  Pour  diluted  sulphuric  acid  upon 
zinc,  leaving  the  zinc  in  excess.  After  the  action 
ceases,  pour  off  the  clear  liquid,  which  is  the  white 
vitriol  in  solution.  If  this  be  evaporated  slowly, 
crystals  will  he  formed. 

Application.  By  a  similar  process  the  white 
vitriol  of  the  shops  is  manufactured. 

The  sulphuret  of  zinc,  blende,  is  found  in  South 
Hampton  mines  and  other  parts  of  New-England 
and  the  calamine  is  found  in  New-Jersey. 

PRINCIPLE  5.     CADMIUM. 

Natural  History  and  general  Remarks. 

Cadmium  was  lately  discovered  by  Stromeger 
in  carbonate  of  zinc.  It  has  been  found  in  silici- 
ous  oxid  of  zinc  in  Derbyshire.  Probably  it  may 
be  found  in  the  silicious  oxid  in  Massachusetts. 
It  resembles  tin  in  not  being  oxidated  at  the  com- 
mon temperature,  in  being  flexible  and  ductile.  It 
is  harder,  however,  and  more  tenaceous.  It  is 
precipitated  by  zinc  in  a  foliacious  form;  like 
lead. 

Should  it  ever  be  found  in  large  quantities,  it 
would  be  useful  as  a  paint  in  the  state  pf  a  sulphu- 
ret, of  a  lemon  yellow  colour. 

SECTION  2.  METALS  WHICH  ABSORB  OXYGEN, 
BUT  NOT  WITH  SUFFICIENT  FORCE  TO  DECOMPOSE 
WATER  ;  AND  FROM  WHICH  OXYGEN  CANNOT  BE 
EXTRICATED  BY  HEAT  ALONE. 

(May  become  acids  capable  of  combining  with 
salifiable  bases. ) 


ITS  CLASS    V.       METALS. 

General  Remarks. 

Five  of  the  metals  of  this  section  may  themselves 
become  acids,  and  unite  with  other  metals  anil 
with  metalloids  ;  not  as  alloys,  but  as  acids  form- 
ing salts  with  them.  The  other  seven  cannot  be- 
come acids.  Copper  is  more,  useful  in  the  arts, 
than  all  the  other  eleven  metals  of  the  section. 

PRINCIPLE  6.     ARSENIC. 
Natural  History  and  general  Remarks. 

Arseniate  of  cobalt  is  not  uncommon  in  the  horn 
blend  rocks  of  this  country.  It  is  found  in  Hun- 
gary, &c.  in  the  state  of  a  red  sulphuret,  called 
realgar ;  and  in  the  state  of  a  yellow  sulphuret. 
called  orpiment.  Numerous  combinations  of  this 
metal  in  the  state  of  arsenious  and  arsenic  acids, 
are  given  in  the  large  works  on  chemistry.  It  is 
a  deadly  poison  in  the  state  of  arsenious  acid, 
which  is  the  solid  substance  commonly  called  the 
white  oxid  of  arsenic. 

Prop.  I.  Arsenic  may  be  united  with  sulphur, 
forming  artificial  orpiment. 

Illustration.  Dissolve  the  arsenious  acid  in  mu- 
riatic acid.  Pour  into  this  solution  water  well 
charged  with  sulphuretted  hydrogen.  A  yellow 
precipitate  of  that  variety  of  sulphuret  of  arsenic, 
called  orpiment,  falls  down  in  a  powder. 

Application.  Orpiment  is  used  in  the  arts  for 
an  orange  pigment.  It  is  a  beautiful  mineral, 
either  native  or  artificial. 

Prop.  2.  Jlrsenious  acid  when  thrown  on  ignit- 
ed charcoaly  gives  off  the  scent  of  garlic. 


PRINCIPLE    6.      ARSENIC.  179 

Illustration.  Take  burning  coals  upon  a  shov- 
el, and  sprinkle  pulverized  common  arsenic  of  the 
shops  upon  it.  White  fumes  will  arise,  which 
give  the  smell  of  garlic. 

It  is  now  well  understood,  that  before  the  smell 
of  garlic  can  be  produced,  the  arsenious  acid  must 
be  converted  into  metallic  arsenic,  and  in  a  state 
of  sublimation.  Its  projection  on  red  hot  char- 
coal will  produce  this  effect,  by  its  giving  off  its 
oxygen  to  the  charcoal  and  becoming  heated  by 
it. 

Application.  As  no  metal  gives  a  similar  odour, 
this  is  a  conclusive  test,  when  we  are  sure  that  no 
animal  or  vegetable  matter  is  present. 

Prop.  3.  Arsenious  acid  may  be  detected  lyj)e- 
ing  reduced  to  the  solid  metallic  state,  or  by  tests 
in  the  liquid  state.* 

Illustration.  1.  Mix  arsenious  acid,  in  the  pul- 
verized state,  with  three  times  its  weight  of  black 
flux,  and  put  the  mixture  into  a  glass  tube  closed 
at  one  end,  (a  long  test  glass  is  best)  from  three  to 
six  inches  long,  and  the  fourth  of  an  inch  in  dia- 
metre.  Apply  the  heat  of  spirit  or  of  an  Argand's 
lamp  (hot  coals  will  do)  to  the  closed  end.  In  a 
short  time  the  metallic  arsenic  will  appear  in  a 
brilliant  form  on  the  inner  surface  of  the  tube. 

2.  Dissolve  arsenious  acid  in  pure  water  by  the 
application  of  a  gentle  heat.  To  the  solution  add 
sulphuretted  hydrogen  gas  in  solution,  which  has 
been  made  but  a  few  minutes.  An  orange  colour- 
ed precipitate  will  be  produced. 

"This  proposition,  together  with  its  illustration  and  application, 
were  obligingly  furnished  by  Dr.T.  Romeyn  Beck,  author  of  the  work 
on  Medical  Jurisprudence.  I  sake  the  liberty  to  add,  that  no  physi- 
cian, lawyer  or  judge,  who  has  any  respect  for  his  own  reputation,  or 
for  truth,  ought  to  undertake  any  investigation,  where  human  life  or 
liberty  is  concerned,  without  studying  that  work. 


180  CLASS    V.      METALS. 

3.  To  a  similar  solution  of  the  arsenioas  acid, 
add  a  solution  of  carbonate  of  potash,  to  this  mix- 
ture add  a  solution  of  sulphate  of  .copper.     A  pre- 
cipitate of  a  peculiar  green  will  appear,   called 
Scheele's  green.     [See  Copper.] 

4.  In  a  similar  solution  of  arsenious  acid,  bring 
two  glass  rods  into  contact,  the  one  having  been 
dipped  in  pure  liquid  ammonia  and  the  other  into 
a  solution  of  nitrate  of  silver.     A  bright  yellow 
precipitate  will  appear  at  the  point  of  contact. 

Application.  These  are  the  leading  decisive 
tests  of  the  presence  of  the  deadly  poison,  called 
arsenic  or  ratsbane.  It  should  be  remarked, 
that  great  difficulties  occur  in  the  examination  of 
it,  when  mixed  with  human  fluids.  This  is  gen- 
erally the  case  in  accusations  of  poisoning.  The 
usual  articles  of  food  and  drink  often  impair  the 
correctness  and  vary  the  result  of  these  tests.  It 
must  also  be  observed,  that  in  some  cases  of  real 
poisoning,  none  can  be  detected  ;  owing  probably, 
to  its  having  been  evacuated  by  vomiting. 

No  one  ought  ever  to  undertake  the  investiga- 
tion of  a  case  of  supposed  poisoning,  who  is  not 
perfectly  familiar  with  the  ordinary  effects  of  tests 
on  arsenic — nor  even  then  should  he  proceed  to 
an  examination  without  accompanying  every  step 
with  a  similar  collateral  experiment  upon  a  speci- 
men known  to  be  arsenic. 

PRINCIPLE  7.     CHROME. 
Natural  History  and  general  Remarks. 

Chrome  is  found  in  the  state  of  an  acid,  com- 
bined with  iron,  called  chromate  of  iron.  It  is 
generally  found  in  talcose  rocks,-  or  in  granular 


PRINCIPLE    S.       MOLYBDENA.  181 

lime  rocks,  which  contain  serpentine.  It  is  most 
abundant  near  Baltimore  in  Maryland  ;  but  is 
found  in  the  granular  lime  rock  at  different  inter- 
vals from  near  New-Haven  in  Connecticut  to 
Canada. 

When  chromate  of  iron  is  pulverized  and  mixed 
with  nitrate  of  potash,  and  heated  to  redness,  a 
double  decomposition  takes  place,  and  the  chro- 
mate of  potash  is  produced. 

Chromate  of  potash  is  decomposed  ly  metallic 
salts.  ' 

Illustration.  Dissolve  chromate  of  potash  in 
pure  water.  Pour  some  of  it  in  a  solution  of  sugar 
of  lead,  and  the  beautiful  yellow  pigment,  chro- 
mate of  lead,  will  be  precipitated.  Pour  it  into 
nitrate  of  mercury,  cinnabar  red  is  produced. 
Into  nitrate  of  silver,  and  carmine  red  is  produc- 
ed. 

Application.  The  chromate  of  lead  is  now  in 
general  use  as  a  yellow  paint.  An  exceedingly 
small  quantity  of  the  chromate  of  lead  mixed  with 
white  lead,  gives  the  whole  a  beautiful  yellow 
colour. 

PRINCIPLE  8.     MOLYBDENA. 

Natural  History  and  general  Remarks. 

Molybdena  is  found  in  the  state  of  a  sulphuret 
in  rocks  of  granite  and  gneiss  in  numerous  locali- 
ties in  the  United  States.  It  has  the  appearance 
of  plumbago,  but  may  be  easily  distinguished 
from  that  mineral  with  the  blow-pipe.  It  gives 
off  the  smell  of  sulphur,  and  does  not  burn  ; 
whereas  plumbago  burns  under  a  strong  flame 

16 


182  CLASS    V.      METALS. 

from  the  blow-pipe,  and  does  not  give  off  the  sul- 
phurous smell.  It  is  reduced  to  the  metallic  state 
with  much  difficulty.  It  is  then  soluble  in  no  acid 
but  nitric  and  nitro-muriatic.  It  is  not  used  in 
the  arts. 

PRINCIPLE  9.     TUNGSTEN. 
Natural  History  and  general  Remarks. 

It  is  found  in  rocks  of  granite  and  gneiss  in 
Huntington  in  Connecticut,  in  the  state  of  an  oxid. 
Also  in  Sweden  and  other  places.  It  is  scarcely 
soluble  in  nitric  acid,  and  not  at  all  in  any  other 
acid.  It  is  scarcely  fusible  in  very  high  heat.  It 
is  capable  of  uniting  with  most  other  metals  in  the 
state  of  an  acid.  It  is  not  used  in  the  arts. 

PRINCIPLE  10.     COLUMBIUM. 
Natural  History  and  general  Remarks. 

Columbhim  has  been  found  in  the  state  of  an 
oxid  in  Sweden  and  in  America.  Berzelius  has 
lately  discovered  it  in  the  granite  of  Haddam  in 
Connecticut,  which  was  sent  to  him  by  Mr.  P  ierce. 
The  small  black  or  very  dark  brown  specks,  which 
we  have  considered  as  a  very  singular  kind  of 
shorl,  he  has  analyzed  and  found  it  to  be  the  ore 
of  Columbium.  Though  it  may  be  alloyed  with 
iron  and  tungsten,  it  has  not  hitherto  been  dissolv- 
ed in  any  acid.  It  is  not  used  in  the  arts. 

(Not  capable  of  becoming  acids.} 

PRINCIPLE  11.     COPPER. 
Ntttural  History  and  general  Remarks. 
Copper  is  found  native  in  many  places.    It  ift 


PRINCIPLE   11.       COPPER.  183 

pretty  common  in  the  state  of  a  sulplmret  and 
a  carbonate.  It  is  chiefly  manufactured  from  the 
copper  pyrites,  found  in  primitive  rocks.  But  it  is 
found  in  all  the  geological  classes  of  rocks.  Cop- 
per alloyed  with  from  12  to  18  per  cent  of  zinc 
forms  brass.  When  the  proportion  of  copper  is 
larger  it  forms  pinchbeck.  Six  parts  of  copper, 
two  of  tin,  and  one  of  arsenic,  form  speculem  met- 
al. Three  parts  of  copper  with  one  of  tin,  form 
bell  metal  ;  and  for  little  shrill  sleigh-bells,  &c.  a 
little  zinc  is  added.  Copper  and  tin  form  bronze 
also,  consisting  of  ten  parts  of  copper  to  one  of  tin, 
Jt  is  much  used  in  the  arts. 

Prop.  1.  Copper  long  exposed  to  moisture  in 
a  damp  place,  becomes  a  green  carbonate  at  the 
surface. 

Illustration.  Scrape  off  the  green  crust  from  a 
piece  of  copper  and  pour  muriatic  acid  upon  it, 
and  it  will  effervesce,  by  the  escape  of  carbonic 
acid.  Pure  copper  will  not  effervesce,  which  may 
be  shown  also. 

Application.  All  copper  and  brass  utensils 
should  be  defended  from  moisture  by  tinning  or 
by  careful  cleaning  ;  for  the  carbonate  of  copper 
is  very  injurious  if  taken  into  the  stomach. 

Prop.  2.  Copper  combines  with  sulphuric  acid 
and  forms  sulphate  of  copper,  called  blue  vitriol  or 
lloman  vitriol. 

Illustration.  Boil  copper  filings  in  sulphuric 
acid,  and  the  salt  will  be  formed  in  the  liquid 
state.  This  may  be  evaporated  in  the  usual  way. 

Application.  On  this  principle  the  blue  vitriol 
of  the  shops  is  made  ;  but  not  by  a  similar  opera- 
tion. The  native  sulplmret  is  heated  and  expos- 


184  CLASS    V.      METALS. 

ed  to  air  and  moisture,  and  thereby  the  peroxid  is 
obtained.  Then  the  salt  is  readily  formed  by 
pouring  sulphuric  acid  upon  it. 

Prop.  3.  Vinegar  will  both  oxidate  copper  and 
form  with  it  the  salt  called  verdigris,  (or  acetate 
of copper. ) 

Illustration.  Cover  a  gallipot  of  warm  vinegar 
\vith  a  polished  piece  of  sheet  topper.  After  some 
time  it  will  be  covered  with  a  thin  crust  of  verdi- 
gris. It  is  best  for  standing  several  hours,  after 
cooling. 

Application,  Upon  this  principle,  though  with 
very  different  apparatus,  the  verdigris  of  the  shops 
is  made. 

Prop.  4.  Copper  has  a  strong  affinity  for  am- 
monia, with  which  it  will  combine  when  in  the  state 
of  salts  or  otherwise,  and  form  various  coloured 
compounds. 

Illustration.  Rub  together  in  a  mortar  about 
equal  bulks  of  sulphate  of  copper  and  carbonate 
of  ammonia.  A  purple  compound  will  be  formed. 

Application.     This  is  the  ammoniuret  of  cop 
per  used  in  medicine. 

Prop.  5.  Copper  combines  with  arsenipus  acid 
and  forms  Scheele's  green. 

Illustration.     This  may  be  effected  by  a  double 
decomposition.     Form  arseniate  of  potash  by  dis- 
solving pearlash  in  water  and  heating  it,  then  by 
dropping  in  any  quantity  of  common  arsenic. — * 
Dissolve  sulphate  of  copper  in  hot  water  also. 
Let  this  preparation  be  made  before  lecture  hour. 
At  the  time  of  lecture,  pour  the  solution  of  sul 
phate  of  copper  into  the  arseniate  of  potash.     Ar 
eeniate  of  copper  and  sulphate  of  potash  will  be 


PRINCIPLE    12.      ANTIMONY.  185 

formed.  The  arseniate  of  copper  will  precipitate, 
and  the  sulphate  of  potash,  with  the  excess  of 
pearlash  or  of  arsenious  acid,  if  any,  will  remain 
in  the  liquid  state.  Pour  off  the  liquid,  and  wash 
the  precipitate  several  times.  This  will  be  the 
true  Schecle's  green. 

Application.  So  much  reliance  is  placed  on 
this  process  as  a  test  for  arsenic,  that  every  stu- 
dent in  chemistry  ought  to  he  well  acquainted  with 
this  colour.  See  article  Arsenic. 

PRINCIPLE  12.     ANTIMONY. 

Natural  History  and  general  Remarks,. 

Antimony  sold  at  the  shops  is  in  the  state  of  a 
sulplmret  generally.  It  exhibits  a  crystalline 
form  ;  being  mostly  in  needle  form  crystals.  It 
lias  been  found  in  very  small  quantities  in  differ- 
ent parts  of  the  United  States.  In  Europe  it  is 
found  mostly  in  primitive  rocks.  It  unites  with 
three  or  four  proportions  of  oxygen,  according  to 
lire  ;  the  peroxid  being  the  crocus  of  antimony  of 
the  shops. 

When  taken  into  the  stomach  in  almost  any 
form  it  causes  vomiting.  It  does  not  contract  so 
much  on  cooling  as  most  other  metals  ;  it  is  there- 
fore useful  in  the  manufacture  of  printers'  types. 

Prop.  1.  S.ulphuret  of  antimony  will  decom-> 
pose  water  and  form  sulphuretted  hydrogen  gas. 

Illustration.  Pulverize  the  common  sulphtiret 
of  antimony,  and  put  it  into  a  retort.  Pour  in  wa^ 
ter  and  dilute  muriatic  acid,  apply  heat  and  col- 
lect the  gas;  as  directed  under  sulphuretted  hydro- 
gen  gas. 


186  CLASS    V.      METALS. 

Application.  When  we  wish  for  a  test  in  haste, 
it  is  often  a  convenience  to  apply  the  sulphuret  of 
antimony,  without  the  trouble  of  preparing  the 
sulphuret  of  iron. 

Prop.  2.     Sulphuret  of  antimony  may  be  reduc- 
ed to  the  state  of  the  peroxid  of  antimony  by  heat 
ing  with  saltpetre  and  sulphuric  acid. 

Illustration,  Pulverize  very  finely  sulphuret 
of  antimony  and  saltpetre.  After  pulverizing,  mix 
the  two  powders  very  intimately  in  the  proportion 
of  one  of  antimony  to  five  or  six  of  the  salt.  Throw 
the  mixture  all  at  once,  into  a  crucible  previously 
heated  to  whiteness.  Deflagration  will  immedi- 
ately take  place,  during  which  oxygen  will  be  giv- 
en oft*  by  the  saltpetre  to  the  sulphur  and  convert 
chief  of  it  into  sulphurous  acid  ;  and  to  the  auti 
mony,  and  convert  most  of  it  into  an  oxid.  Now 
take  off  the  crucible,  let  it  cool,  select  all  the  orange 
yellow  part  of  its  contents  and  reject  the  rest. 
This  is  what  is  called  in  medicine  crocus  of  anti- 
inonij)  or  sometimes  the  metallic  antimony.  Though 
it  is  not  entirely  separated  from  the  sulphur,  it  is 
sufficiently  pure  for  common  purposes. 

Now  mix  this  crocus  of  antimony  with  about 
twice  its  weight  of  sulphuric  acid  in  a  gallipot  or 
tea-cup.  After  mixing  and  remaining  a  little 
while,  put  it  into  a  clean  iron  ladle,  and  boil  it 
down  to  a  perfectly  dry  mass,  frequently  stirring 
it  with  an  iron  rod.  This  dry  powder,  when  well 
washed,  is  nearly  pure  peroxid  of  antimony. 

Application.    When  antimony  is  brought  to  the 
state  of  an  oxid,  it  is  in  a  convenient  state  for  ap- 
plying to  various  uses.    It  may  easily  be  prepared 
for  alloying  with  lead  for  the  manufacture  of  print 
ing  types,  &c. 


PRINCIPLE    13.      BISMUTH.  187 

Prop.  3.  Oxid  of  antimony  will  combine  with 
iartaric  acid,  and  form  the  tartrate  of  antimony ; 
called  tartar -emetic. 

^Illustration.  Dissolve  some  supertartratc  of 
potash  (to  be  described  under  vegetable  acids)  in 
water,  and  put  into  it  an  equal  weight  of  dry  oxid 
of  antimony.  Pour  this  mixture  into  a  clean  iron 
ladle,  and  boil  it  about  fifteen  minutes.  Let  it 
stand  about  a  minute  to  settle  any  impurities,  and 
then  pour  the  liquid  into  any  clean  vessel  to  set  by 
to  crystallize.  Or  it  may  be  cleaner  to  strain  it 
through  paper.  After  it  cools  and  stands  awhile 
crystals  of  tartrate  of  antimony  will  be  formed. 
The  supernatant  liquid  may  be  poured  off  and 
evaporated  a  little,  and  set  away  to  crystallize 
again.  These  crystals  may  be  washed  and  put 
up  for  use. 

Application.  This  is  the  important  medicine  so 
long  in  use,  under  the  name,  tartar- emetic.  It  is 
rendered  more  pleasant,  by  dissolving  the  crystals 
in  boiling  water,  equal  to  about  fifty  times  their 
weight.  Then  adding  about  a  third  more  good 
wine  than  to  equal  the  quantity  of  boiling  water, 
This  is  called  tartarized  wine. 

PRINCIPLE  13,     BISMUTH, 
Natural  History  and  general  Re?narks. 

Bismuth  is  found  in  a  pure  metallic  state  in  Hun- 
tington,  Connecticut.  A  pretty  large  specimen 
was  found  among  the  pebbles  in  a  stream  of  water 
near  Lake  George.  It  is  found  in  mines  of  .gold;' 
with  copper,  &c.  but  is  not  very  abundant. 

Prop.  1.    JBismnth  combines  with  nitric  acid, 


188  CLASS   V.      METALS. 

find  forms  nitrate  of  bismuth  ;  the  most  delicate 
sympathetic  ink. 

Illustration.  Whittle  off  a  little  bismuth  into 
a  wine-glass.  Drop  in  a  little  common  nitric  acid 
diluted  with  half  as  much  water.  Violent  action 
will  commence ;  when  it  ceases  the  nitrate  will  be 
found  in  the  liquid  state. 

Dip  a  dean  pen  into  it  and  write  as  with  ink. 
Hold  the  paper  near  a  fire,  but  not  so  near  as  to 
heat  it,  the  letters  will  become  invisible.  Having 
shewn  the  paper  to  the  class  without  any  visible 
letters,  now  dip  it  into  water,  or  hold  it  in  steam 
over  boiling  water,  and  on  taking  it  out  the  letters 
will  become  visible  and  appear  as  if,  written  with 
pale  ink. 

Application.  If  a  letter  be  written  on  ordinary 
subjects  with  ink,  sentiments  of  a  more  delicate 
nature,  expressive  of  sympathies  which  it  is  desir- 
able to  conceal  from  prying  post-office  clerks,  &c0 
may  be  expressed  in  this  liquid  between  the  ink 
lines.  The  confidential  correspondent  has  only 
to  dip  the  letter  in  water  before  he  may  catch  the 
fugitive  sigh  and  feast  his  fervid  imagination  on 
the  half- told  assurances.  Hut  the  writing  will 
soon  disappear,  and  leave  not  a  vestige  to  prove  n, 
forgotten  promise. 

Prop.  2.  Water  precipitates  oxid  of  bismuth 
from  liquid  nitrate  of  bismuth.* 

Illustration.  Pour  into  the  liquid  nitrate  of  bis- 
jnuth,  prepared  as  in  the  last  experiment,  eight  or 
ten  times  its  bulk  of  water,  and  the  white  oxid 
will  be  precipitated  in  a  fine  powder. 

Application.  This  white  oxid,  after  being  wash" 
eil  and  dried,  is  put  up  for  medical  use.  It  is 

*  This  experiment  with  antimony  will  give  the  same  result. 


PRINCIPLE    14.      COBALT.  189 

said  to  be  an  excellent  tonic.  It  forms  the  basis 
of  the  most  delicate  face  paints,  or  pigments  for 
other  uses.  But  it  is  so  readily  tarnished  by  sul- 
phuretted hydrogen,  that  a  painted  face,  where  it 
has  been  applied,  will  become  tawny  at  the  ap- 
proach of  a  small  quantity  of  that  gas.  Conse- 
quently those  who  wear  painted  faces  have  two 
good  reasons  for  retreating  from  the  attack  of  nan 
seous  scents. 

Remark.  *  The  other  five  metals  belonging  to 
this  division  of  the  second  section,  need  not  be  in- 
troduced for  experiments  in  the  course  proposed. 
Instructors  who  think  proper  to  experiment  upon 
them,  are  referred  to  larger  works. 

PRINCIPLE  14.     COBALT. 

Natural  History  and  general  Remarks. 

Cobalt  is  found  combined  with  arsenic  and  with 
sulphur  in  hornblende  rock,  and  in  the  same  rock 
passing  into  gneiss,  from  Vermont  to  Long  Island 
sound,  passing  down  on  the  east  side  of  Connec- 
ticut river  to  near  Haddam  in  Connecticut,  and 
then  crossing  to  the  west  side.  Though  this  range 
is  very  extensive,  it  has  never  been  found  in  it  in 
sufficient  quantities  for  working. 

It  is  sold  in  the  shops  in  the  state  of  an  imper- 
fect oxid,  called  zaffre.  The  pure  metal  s  red- 
dish grey. 

Prop.  1.  The  xaffre  gives  to  .glass  or  to  an  al 
kali  a  violet  blue  colour. 

Illustration.  Mix  finely  pulverized  flint  and 
borax  and  put  in  a  small  quantity  of  zaffre.  Melt 
this  mixture  with  pretty  strong  heat  in  a  crucible  ; 


190  CLASS    V.      METALS. 

and  a  small  blue  glass  will  be  produced.  Or  put 
a  little  zaffre  in  borax  alone,  or  in  pearlash,  and 
melt  the  mixture. 

Application.  The  smalt  sold  in  the  shops  in 
powder,  is  merely  pulverized  glass  prepared  as 
above. 

Prop.  2.  JL  blue  or  green  sympathetic  ink  is 
made  with  zaffre  and  muriatic  acid. 

Illustration.  Drop  a  tea-spoon  of  zaffre  into 
the  third  of  a  wine-glass  of  nitro-muriatic  acid. 
After  standing  a  while,  write  on  paper.  The  writ- 
ing will  he  invisible  cold,  but  on  heating  the  paper 
the  writing  will  be  blue  unless  there  is  a  little  iron 
in  the  zaffre,  which  will  give  it  a  green  hue.  If  a 
little  common  salt  in  solution  had  been  added,  the 
writing  would  disappear  on  removing  from  the 
fire. 

Application.  This  has  no  farther  application, 
than  as  it  illustrates  the  colouring  properties  of 
the  oxids  of  metals. 

PRINCIPLE  15.     TITANIUM. 
Natural  History  and  general  Remarks. 

*  Titanium  is  always  found  in  the  state  of  an  oxid 
in  primitive  rocks,  particularly  with  tremolite  in 
granular  limestone.  It  was  considered  as  a  sub- 
species of  shorl  until  within  twenty  or  twenty-five 
years.  It  is  always  brownish  red,  very  difficult 
to  reduce,  and  its  properties  little  known.  Excel- 
lent crystals  are  found  between  Greenfield,  Mas- 
sachusetts, and  the  Green  Mountain  range.  Sev- 
eral localities  have  been  discovered  in  that  dis- 
trict, 


PRINCIPLE    19.       GOLD.  191 

PRINCIPLE  16.     TELLURIUM. 
Natural  History  and  general  Remarks. 
Tellurium  is  found  in  Huntington  in  Connect! 
cut,  associated  with  tungsten,  bismuth  and  silver. 
It  is  always  more  or  less  alloyed  with  other  met- 
als.    It  is  chiefly  found  in  Transylvania. 

It  resembles  antimony  considerably.  It  burns 
with  a  bluish  flame  before. the  blow-pipe,  giving 
the  odour  of  horse  radish.  Not  used  in  the  arts, 

PRINCIPLE   17.     CERIUM. 
Natural  History  and  general  Remarks. 

Cerium  is  found  in  Sweden  in  the  state  of  an 
oxid.  The  protoxid  is  white,  the  peroxid  is  red. 
It  has  scarcely  ever  been  reduced  to  the  metallic 
state.  The  peroxid  is  generally  combined  with 
silex.  It  is  not  used  in  the  arts  ;  and  scarcely 
known  in  the  laboratory  or  the  cabinet. 

PRINCIPLE  18.     URANIUM. 

Natural  History  and  general  Remarks. 
Uranium  is  found  in  the  state  of  a  black  oxid 
and  of  a  green  oxid.  It  is  found  hi  small  masses 
in  veins  of  ores  in  primitive  rocks  in  Maryland 
and  in  some  parts  of  Europe.  The  green  oxid  is 
a  beautiful  mineral ;  but  it  is  extremely  difficult  to 
reduce  either  of  the  oxids  to  the  metallic  state.  It 
is  not  used  in  the  arts. 

SECTION  3.     METALS  WHICH  DO  NOT  RECEIVE 
OXYGEN,  EXCEPTING  FROM  STRONG  ACIDS. 

PRINCIPLE  19.     GOLD. 

Natural  History  and  general  tiemarks. 
Gold  is  never  found  mineralized;  but  almost  al- 


192  CLASS    Y.      METALS. 

/ways  in  the  state  of  an  alloy  with  silver  or  with 
some  other  metal.  It  is  found  in  most  countries 
in  the  sands  of  rivers  ;  but  when  found  in  place 
it  is  generally  contained  in  primitive  rocks.  It  has 
lately  been  found  in  considerable  quantities  in 
"North  Carolina ;  a  particular  description  of  that 
locality  has  been  communicated  to  Silliman's 
Journal  by  Professor  Olmsted.  Gold  cannot  be 
tarnished  by  oxidation  on  exposure  to  water  or 
the  atmosphere. 

Prop.  1.  (fold  may  be  dissolved  by  nitro-mnri- 
atic  and  by  oxy-muriatic  acids,  and  by  no  other 
acid. 

Illustration.  Put  a  little  muriatic  acid  into  a 
wine-glass,  and  twice  as  much  nitric  acid  in  anoth- 
er wine-glass.  Drop  into  each  a  small  piece  of 
gold  leaf,  and  neither  of  the  pieces  will  be  dissolv- 
ed. Now  pour  the  contents  of  one  glass  into  the 
other,  and  both  pieces  of  gold  will  be  immediately 
dissolved. 

Application.  This  mixture  is  the  aquaregia 
of  old  authors.  The  new  compound  formed  is 
muriate  of  gold ;  but  it  seems  that  gold  requires 
the  joint  action  of  the  two  acids,  the  nitric  acid 
affording  oxygen  for  oxidating  the  gold,  and  then 
the  muriatic  acid  unites  with  it. 

Prop.  2.  Iron,  silver  and  copper  may  be  cov- 
ered with  a  thin  coat  of  gold,  which  is  called  gild- 
ing. 

^Illustration.  Pour  into  a  saturated  solution  of 
muriate  of  gold  (that  is,  where  there  is  no  excess 
of  acid)  about  twice  as  much  sulphuric  ether. 
Now  brush  upon  a  clean  polished  surface  of  iron 
or  steel  some  of  this  liquid.  The  ether  will  soon 


PRINCIPLE    19.       GOLD.  193 

evaporate  and  leave  the  gold  covering  the  sur- 
face. 

To  gild  silver  or  copper,  heat  gold  and  mercu- 
ry together  in  a  crucible,  one  part  of  gold  to  about 
eight  of  mercury,  until  they  are  completely  alloy- 
ed ;  then  throw  the  hot  alloy  into  cold  water. 
Having  wet  the  silver  or  copper  with  diluted  ni- 
tric acid,  brush  on  the  alloy  with  a  fine  brush  (a 
wire  brush  is  best)  as  uniformly  as  possible. 
Then  drive  off  the  mercury  with  heat,  placing  the 
gilded  metal  over  hot  coals.  Afterwards  the  sur- 
iace  must  be  polished  with  a  burnisher.  The  only 
objection  made  to  this  method  by  artists  is,  that  it 
is  very  difficult  to  lay  on  the  alloy  evenly.  But 
old  artists  learn  to  brush  over  the  bare  spots  while 
it  is  heating,  being  careful  to  avoid  inhaling  the 
mercurial  fumes. 

Application;  This  method  of  gilding  iron  is 
undoubtedly  very  perfect ;  but  it  is  desirable  that 
some  better  method  for  gilding  the  other  medals 
should  be  devised.  Most  substances  to  be  gilded 
may  be  conveniently  covered  with  gold  leaf.  Gold 
is  so  very  ductile,  that  the  leaves  are  made  very 
thin.  It  is  said  that  about  a  pound  of  gold  may 
be  hammered  out  between  beater's  skins  so  very 
thin,  as  to  furnish  enough  to  gild  a  wire  of  suffi- 
cient length  to  surround  the  earth. 

Prop.  7.  Adulterations  of  gold  coin  may  be  de- 
tected, without  an  analysis,  by  taking  the  specific 
gravity. 

Illustration.  Take  the  specific  gravity  of  a 
piece  of  gold  coin,  according  to  the  directions  giv- 
en in  the  introduction.  If  its  specific  gravity  is 
17.157,  it  is  lawful  coin. 

17 


194  CLASS    V,      METALS* 

Application.  There  is  no  metal  so  heavy  as 
gold,  excepting  platina.  And  such  is  the  value  of 
platina,  that  there  is  no  danger  of  its  being  alloy- 
ed with  that  metal.  Standard  gold  coin  is  an  al- 
loy of  one  of  copper  to  eleven  of  gold,  in  order  to 
make  the  coin  harder,  that  it  may  wear  the  better. 
The  specific  gravity  of  perfectly  pure  gold  is  19.3. 
Copper,  silver,  and  most  other  metals,  which  are 
alloyed  with  gold,  may  be  easily  separated  from' 
gold  by  nitric  acid.  For  if  the  alloy  be  in  fine 
filings,  the  nitric  acid  will  dissolve  the  other  met- 
als, and  leave  the  gold  in  a  black  powder.  This 
powder  may  be  separated  and  melted  down  into  a 
pure  mass.  But  the  most  common  method  adopt- 
ed by  artists  is,  to  melt  the  alloy  with  sulphuret  of 
antimony.  The  other  metals  become  sulphurets, 
and  the  gold  will  unite  with  the  antimony  and  fall 
to  the  bottom  of  the  crucible.  After  cooling  it  may 
be  separated.  Now  melt  the  alloy  of  gold  and  an- 
timony, boil  it  at  a  white  heat,  and  the  antimony 
will  become  volatilized  and  fly  off. 

PRINCIPLE  20.     SILVER. 

Natural  History  and  general  Remarks. 

Silver  is  found  alloyed  and  mineralized  with 
numerous  substances.  Sulphur,  aluruine,  anti* 
mony,  lead,  arsenic,  silver,  copper,  mercury,  car- 
bonic acid,  muriatic  acid,  &c.  have  been  found 
combined  with  silver.  A  little  silver  appears  in 
most  lead  mines  ;  with  this  exception  silver  is  a 
rare  ore  in  North  America.  It  is  very  abundant 
in  South  America,  where  it  is  found  in  the  metal- 
liferous limestone. 

Silver  cannot  be  tarnished  with  oxygen  by  any 


PRINCIPLE  20.       SILVER.  195 

exposure  at  the  common  temperature.     It  is  very 
malleable  and  ductile,  but  not  so  ductile  as  gold. 

Prop.  1.  Silver  coin  is  alloyed  with  copper,  as 
12  J  to  1 ;  from  which  alloy  silver  may  be  obtained 
pure,  by  forming  a  nitrate  of  it,  and  then  precipit- 
ating it  by  solid  metallic  copper. 

Illustration.  Put  some  nitric  acid  into  a  wine- 
glass diluted  with  an  equal  bulk  of  water.  Drop 
into  it  a  six  cent  piece,  and  let  it  remain  until  ac- 
tion ceases.  Now  takeout  the  undissolved  silver, 
and  put  in  a  plate,  or  a  cent,  of  perfectly  clean 
bright  copper.  The  silver  will  be  precipitated 
after  a  short  time.  Wash  the  powder  several 
times  ;  and  put  a  little  liquid  ammonia  into  the 
water  for  the  first  washings.  Now  melt  down 
ihe  powder  into  a  solid  mass,  which  will  be  pure 
silver. 

Application.  It  is  very  convenient  to  have  a 
ready  method  for  obtaining  pure  silver  from  coin 
when  it  is  wanted  for  a  particular  purpose.  But 
silver  is  harder  and  will  wear  longer  if  it  contains 
a  little  copper.  Ever  so  small  a  quantity  of  cop- 
per, however,  in  a  finger  ring  or  in  any  jewelry, 
which  comes  in  contact  with  the  skin,  will  tarnish, 

Prop.  2.  Silver  will  combine  with  nitric  acid 
and  form  the  nitrate  of  silver,  called  lunar  caustic? 
or  lapis  infernalis. 

Illustration.  Put  nitric  acid  into  a  wine-glass 
diluted  as  before.  Drop  in  a  piece  of  pure  silver, 
and  let  it  remain  till  action  ceases.  Take  out  the 
remainder  of  the  silver.  Evaporate  the  solution  to 
a  solid  salt. 

Application.  This  salt  is  used  in  medicine,  and 
for  a  test  of  the  presence  of  muriatic  acid  in  miu- 


196  CLASS    V.       METALS. 

eral  waters,  &c.  An  indelible  ink  is  also  made, 
by  dissolving  it  in  pure  water  and  then  adding  a 
little  vinegar,  also  adding  a  little  gum-arabic  to 
give  it  consistency.  If  a  piece  of  cotton  or  linen 
be  dipped  into  a  weak  solution  of  pearlasb,  and 
then  dried  under  a  moderately  heated  smoothing 
iron,  it  may  be  written  on  with  a  clean  pen  dipped 
In  this  solution,  and  the  writing  will  never  wash 
out.  Those  who  do  not  wish  to  take  the  trouble 
to  make  the  lunar  caustic,  may  always  iind  it  at 
every  druggist's  shop. 

Prop,  3.  Copper  may  be  coated  with  silver,  if 
nMed  with  it  when  in  the  state  of  a  powder  com- 
bined with  some  of  the  salts. 

^Illustration.  Make  a  powder  as  follows  :  take 
a  few  grains  of  silver  in  powder,  as  precipitated  by- 
copper  In  the  first  experiment,  after  it  is  washed 
and  before  melting — about  an  equal  weight  of 
alum  or  a  little  more — six  times  as  much  table 
salt — also  six  times  as  much  tartrate  of  potash. 
Pulverize  all  these  articles  and  rub  them  well  to- 
gether. Rub  the  clean  bright  surface  of  a  piece  of 
copper  with  this  powder  and  it  will  be  silvered. 

Application.  Though  this  silvering  is  not  very 
durable,  it  will  defend  the  surface  of  copper  from 
tarnishing  while  it  lasts  ;  and  it  may  be  easily  re- 
newed. Plating  copper  is  much  preferable.  This 
is  done  by  brazing  on  a  thin  bar  of  silver  upon  a 
thick  bar  of  copper.  Then  both  are  rolled  out 
Into  the  proper  thickness  for  use. 

Prop.  4.  Horn-silver  of  the  shops  is  formed  lij 
an  oxid  of  silver  and  muriatic  acid. 

Illustration.  Pour  muriatic  acid  into  a  solution 
of  nitrate  of  silver, 


PRINCIPLE    20.      SILVER.  197 

Application.  If  this  salt  is  well  prepared,  so 
as  to  be  almost  a  pearl  white,  it  will  become  violet 
and  then  black,  if  exposed  to  the  sun's  rays  in  a 
thin  test-glass — a  good  illustration  of  the  decom- 
posing power  of  light. 

Prop.  5.  Nitrate  of  silver  heated  with  alcohol 
and  an  additional  portion  of  nitric  acid,  may  be 
formed  into  an  explosive  or  fulminating  powder. 

•^Illustration.  Pulverize  a  very  few  grains  of 
lunar  caustic  of  the  shops.  Put  it  into  a  florence 
flask,  and  add  about  live  times  as  mm  h  alcohol 
and  about  five  times  as  much  strong  nitric  acid. 
If  a  pretty  violent  effervescence  does  not  commence 
soon,  apply  the  heat  of  a  candle.  As  soon  as  it 
does  commence,  remove  the  candle.  As  soon  as  a 
thick  white  precipitate  commences,  the  efferves- 
cence may  be  regulated  by  occasionally  pouring 
in  a  little  pure  water.  After  the  action  has  ceased 
let  it  stand  and  settle  a  short  time ;  then  pour  off 
the  supernatant  liquid  and  wash  the  powder  sev- 
eral times  in  pure  water.  Spread  it  on  paper  and 
let  it  dry  and  drain  awhile.  Now  put  a  grain  of 
it  on  the  blade  of  a  case  knife  and  hold  it  over  a 
candle.  As  soon  as  the  knife  is  a  little  heated  it 
will  explode.  It  will  also  explode  violently  by 
compression  or  friction. 

Application.  This  is  an  interesting  illustration 
of  the  wonderful  force  exerted  when  solids  are  sud- 
denly converted  into  gases.  But  this  preparation 
ought  not  to  be  made  before  a  class  ;  neither  ought 
it  to  be  exhibited  in  the  course  proposedhere.  I 
give  the  description  of  Mr.  Silliman's  method,  for 
the  amusement  of  those  who  have  leisure  to  attend 
to  it  in  a  private  office.  It  is  the  most  powerful 

,17* 


198  CLASS   V.      METALS. 

and  the  most  dangerous  of  all  known  fulminating 
substances. 

PRINCIPLE  21.    PLATINA. 
Natural  History  and  general  Remarks. 

Platina  has  always  been  found  in  small  grains 
in  alluvial  formations  ;  but  from  the  character  of 
the  sands  in  which  it  is  found,  it  is  probable  that 
its  original  associations  are  in  primitive  rocks.  It 
Is  mostly  found  in  South  America.  It  is  never 
found  pure,  but  is  alloyed  with  iron,  copper,  lead, 
osmium,  rhodium,  iridium  and  palladium  ;  though 
these  alloys  constitute  but  a  small  part  of  the  mass 
of  the  ore. 

Platina  is  the  heaviest  of  all  metals,  least  ex- 
pansible by  heat,  most  difficult  to  melt  or  to  unite 
to  oxygen.  It  is  therefore  preferable  to  all  met- 
als for  pendulum  rods,  for  inch  measures,  for  cru- 
cibles, for  reflecting  telescopes,  and  conductors  for 
the  galvanic  battery. 

It  will  be  very  difficult  to  experiment  much  up- 
on platina  in  the  proposed  course.  It  being  the 
most  fixed  and  infusible  of  all  metals,  it  is  pol- 
ished and  used  as  a  concave  reflector  in  the  most 
powerful  telescopes,  where  glass  would  melt  or 
break.  For  crucibles  and  other  uses  it  is  employ- 
ed in  the  laboratory.  It  has  not  been  much  used 
in  the  arts,  on  account  of  its  scarcity. 

Platina  may  be  dissolved  in  nitro-muriatic  acid, 
and  will  then  form  muriate  of  platina,  which  is  a 
test  for  potash. 

^Illustration.  Put  a  grain  or  two  of  platina 
into  a  florence  flask,  and  pour  in  a  small  quantity 
of  nitro-muriatic  acid  and  apply  a  little  heat.  It 


PRINCIPLE   23.      IRIDIUM.  199 

\vill  dissolve  very  slowly  ;  but  in  a  few  days  mu- 
riate of  platina  will  be  formed.  Dissolve  a  little 
muriate  of  soda  (common  salt)  in  a  wine-glass,  and 
a  little  saltpetre  in  another.  Put  a  few  drops  of 
the  muriate  of  platiua  into  each  ;  and  it  will  pro- 
duce no  effect  on  the  solution  of  muriate  of  soda, 
but  will  give  a  yellow  precipitate  from  the  solution 
of  saltpetre. 

Application.  It  is  often  a  convenience  to  be 
able  to  distinguish  potash  from  soda,  without  go- 
ing the  round  of  evaporation  to  dryness,  and  then 
waiting  to  see  whether  it  will  deliquesce  or  efflo- 
resce, 

PRINCIPLE  22.     OSMIUM. 

Natural  History  and  general  Remarks. 

Osmium  is  found  in  small  quantities  alloyed 
with  platina.  A  black  powder  remains  after  dis- 
solving the  grains  of  platina  in  nitro- muriatic  acid. 
If  this  powder  be  heated  with  saltpetre,  the  oxid 
of  osmium  is  sublimed  ;  which  gives  a  very  pun- 
gent odour.  It  is  very  soluble  in  water,  and  be- 
comes purple  with  an  infusion  of  galls.  It  gives 
up  its  oxygen  to  all  the  metals  but  gold  and  pla- 
tina. 

PRINCIPLE  23.     IRIDIUM. 

Natural  History  and  general  Itemarfts. 

Iridium  is  always  alloyed  with  osmium  and  as- 
sociated with  native  platina  of  South  America. 
It  is  scarcely  acted  upon,  or  not  at  all,  by  nitro- 
inuriatic  acid.  By  fusion  with  potash  it  becomes 
oxidated  ;  and  then  it  is  soluble  in  the  three  strong 
acids.  Not  used  in  the  arts. 


CLASS  v.     METALS- 
PRINCIPLE  24.    PALLADIUM. 
Natural  History  and  general  Remarks. 

Palladium  is  found  ingrains  of  platina  and  gold 
in  Brazil.  It  resembles  platina  more  nearly  than 
any  other  metal.  But  its  specific  gravity  is  but 
about  half  that  of  platina.  With  nitro-niuriatic 
acid  it  forms  a  deep  red  solution.  Not  used  in 
Oie  arts. 

PRINCIPLE  25.     RHODIUM. 
Natural  History  and  general  Remarks. 

Hhodium  is  a  doubtful  metal ;  though  Wallas- 
ion  and  Descatils  suppose  they  find  it  sufficiently 
characterized.  Its  specific  gravity  is  about,  half 
that  of  platina.  It  is  not  malleable,  is  infusible 
and  insoluble  in  acids  ;  but  it  is  soluble  in  nitro- 
muriatic  acid  when  alloyed  with  copper,  lead  or 
platina.  Not  used  in  the  arts. 

SECTION  4.    METALS  WHICH  ABSORB  OXYGEN, 

AT  LIMITED  TEMPERATURES,    AND  GIVE  IT  WHOL- 
LY OFF  AT  HIGHER  TEMPERATURES. 

Hemark.  The  character  of  this  section  will  be 
shown  by  heating  red  lead. 

PRINCIPLE  26.     MERCURY. 
Natural  History  and  general  Remarks. 

This' is  the  quicksilver  or  argentum  vivum  of 
old  authors.  It  is  generally  found  in  secondary 
rocks,  in  the  state  of  a  sulphuret,  called  cinnibar* 
It  is  in  the  solid  state  at  about  40  degrees  below 


PRINCIPLE   26.      MERCURY.  201 

zero,  that  is,  about  72  below  freezing — it  is  in  the 
liquid  state  to  about  600  above  freezing,  when  it 
is  evaporated.  It  is  much  used  in  medicine  and 
in  the  arts.  Though  its  most  general  effect  upon 
the  human  system,  when  used  as  a  medicine,  is  to 
correct  the  morbid,  and  restore  the  healthy,  secre- 
tions ;  yet  some  of  its  operations  have  not  hitherto 
been  explained. 

Prop.  I.  The  black  oxid  or  protoxid  of  mer- 
cury is  produced  by  agitating  mercury  in  contact 
with  atmospheric  air,  or  by  precipitating  it  from 
calomel  with  potash. 

Illustration.  The  easiest  method  of  producing 
the  blac  k  oxid  is,  to  put  about  a  gill  by  measure 
of  mercury  in  a  strong  quart  stone  jug,  and  let 
some  person  take  it  into  a  carriage,  who  is  about 
io  travel  forty  or  fifty  miles  over  a  rough  road, 
A  considerable  quantity  of  the  black  oxid  will  be 
formed  in  the  jug.  But  the  mercury  of  the  shops 
is  often  alloyed  with  lead,  which  will  produce  a 
black  powder  in  abundance,  resembling  protoxid 
of  mercury.  The  most  perfect  protoxid  of  mercu- 
ry is  obtained  by  dropping  calomel  into  a  solution 
of  potash. 

Application.     The  black  oxid  formed  in  this 
way  illustrates  the  principle  of  oxidation  very  sat 
isfactorily.     This  is  the  Ethiops  per  se  of  old  au- 
thors. 

Prop.  2.  The  red  oxid  or  per -oxid  of  mercury 
is  produced,  by  heating  mercury  in  contact  with  at- 
mospheric air,  or  by  precipitating  it  from  corrosive 
sublimate. 

Illustration.  Put  a  little  mercury  in  a  florence 
flask  and  keep  it  at  a  beat  a  little  below  boiling 
or  subliming  in  a  sand  bath,  for  several  IIOUFS.  M 


202  CLASS  v.    METALS. 

the  temperature  is  managed  cautiously  it  will  be- 
come a  red  oxid  in  the  form  of  scales  at  first ;  but 
if  the  heat  is  carried  a  very  few  degrees  too  high, 
it  will  sublime  in  the  pure  metallic  state,  accord- 
ing to  the  character  of  this  section.  The  per-oxid 
of  mercury  is  best  obtained  by  precipitating  it  from 
a  solution  of  corrosive  sublimate  by  lime  water. 

Application.  This  was  formerly  called  precipi- 
tate per  se9  as  distinguished  from  the  red  precipi- 
tate. It  is  now  called  hydrargyri  oxydum  rubrum 
in  the  pharmacopoeias. 

Prop.  3.  Mercury  combines  with  nitric  acid 
and  forms  nitrate  of  mercury. 

Illustration,  Put  some  mercury  into  a  wine- 
glass and  pour  in  nitric  acid  diluted  with  about 
one  fourth  its  measure  of  water.  Let  the  mercury 
be  in  excess  and  nitrate  of  mercury  will  form  and 
crystallize,  without  any  evaporation. 

Application.  This  salt  is  used  in  medicine  by 
some  physicians.  It  is  also  used  as  a  test,  and  in 
several  chemical  experiments. 

Prop.  4.     If  a  solution  of  nitrate  of  mercury  be 
poured  into  a  solution  of  phosphate  of  soda,  a  pre 
cipitate  of  phosphate  of  mercury  will  be  formed. 

Illustration.  Dissolve  the  common  phosphate 
of  soda  of  the  shops  in  water.  Pour  into  it  a  so- 
lution of  nitrate  of  mercury,  which  will  instantly 
produce  an  almost  solid  precipitate  of  phosphate 
of  mercury.  For  the  phosphoric  acid  has  a  strong- 
er affinity  for  mercury  than  nitric  acid,  and  nitric 
acid  has  a  stronger  affinity  for  soda  than  phospho- 
ric acid ;  consequently  the  double  decomposition 
is  very  rapid. 

Application.  The  phosphate  of  mercury  is  used 
in  medicine. 


PRINCIPLE   26.      MERCURY. 

Prop.  5.  The  nitrate  of  mercury  may  be  reduc- 
ed by  heat  to  the  nitric  oxid  of  mercury,  called  red' 
precipitate. 

Illustration.  Put  the  salt  into  a  gallipot  and 
apply  a  moderate  heat,  until  it  is  reduced  to  a  dry 
white  or  yellowish  mass.  Then  pulverize  it  very 
finely  in  Wedgewood's  mortar,  and  put  it  into  a  la- 
dle. Raise'the  heat  moderately,  until  the  powder 
becomes  bright  red ;  it  will  then  assume  the  ap- 
pearance of  scales.  It  may  be  heated  to  a  degree 
at  which  it  will  be  red,  then  yellow  on .  cooling^ 
then  red  again,  &c. 

Application.  This  is  the  red  precipitate  used 
in  medicine.  This  is  the  substance  which  is  boil- 
ed with  prussian  blue  to  obtain  the  prussiate  of 
mercury,  from  which  theprussic  acid  is  disengag- 
ed. 

Prop.  6.  Sulphur  and  mercury  will  unite  with- 
out heat  by  being  rubbed  together,  and  form  the 
black  sulphuret,  called  Jlethiops  mineral. 

Illustration.  Put  equal  quantities  by  weight  of 
mercury  and  pulverized  sulphur  in  Wedgewood's 
mortar,  and  rub  them  with  the  pestle  until  there  is 
no  appearance  of  liquid  mercury. 

Application.  This  sulphuret  is  used  in  medi- 
cine. 

Prop.  7.  Mercury  will  combine  with  sulphuric 
acid  by  heat,  and  form  the  per- sulphate  of  mer- 
cury. 

^Illustration.  Put  some  mercury  into  a  flor- 
ence  flask  and  pour  in  about  as  much  strong  sul- 
phuric acid  ;  it  is  better  to  put  in  about  one  eighth 
more  of  the  acid  by  weight.  Set  the  flask  into  the 
lead  pot  or  over  coals  and  boil  the  contents  mo- 


204  CLASS   V.      METALS. 

derately,  until  it  becomes  a  dry  white  mass.  Now 
take  the  flask  from  the  fire  and  cork  it  up  tight,  or 
it  will  absorb  water  very  soon,  from  the  atmos 
phere  and  become  liquid. 

Application.  This  caustic  salt  is  not  much  used 
in  this  state  ;  but  it  is  used  for  making  corrosive 
sublimate  and  calomel.  An  article  in  the  materia 
medica  called  turpetk  mineral  is  made  by  merely 
throwing  this  salt  into  boiling  water,  after  it  is  fine- 
ly powdered.  It  ifttined  lately  becomes  a  yellow 
powder,  and  must  be  washed  several  times  in 
warm  water  before  it  is  put  up  for  use. 

Prop.  8.     If  per -sulphate  of  mercury  and  mu- 
riate of  soda  be  rubbed  together ;  a  double  decompo 
sition  will  take  place,  and  per- muriate  of  mercury y 
called  corrosive  sublimate,  will  be  produced. 

^Illustration.  Put  dry  per-sulphate  of  mercury 
into  Wedgewood's  mortar  and  about  a  third  more 
by  weight  of  common  table  salt.  Hub  them  well 
together,  and  put  the  mixed  powder  into  a  florence 
flask,  stopping  it  loosely  with  a  glass  stopper. 
Set  the  flask  into  the  lead  pot  and  apply  heat.  A 
decomposition  will  take  place,  and  the  corrosive 
sublimate  will  be  sublimed  :  That  is,  by  raising 
the  heat  gradually  it  will  shoot  up  in  crystals 
along  the  sides  and  into  the-  neck  of  the  flask.  Af- 
ter the  crystals  stop  shooting  up,  take  out  the  flask 
and  break  a  hole  through  the-  bottom  carefully, 
still  keeping  it  in  an  upright  position.  The  hole 
must  be  about  as  large  as  the  whole  bottom  of  the 
flask,  through  which  all  the  black  residue  must  be 
discharged.  ISow  scrape  out  the  crystals,  and 
put  them  up  for  use. 

Corrosive  sublimate  may  be  produced  by  mak- 
ing nitrate  of  mercury  with  heat,  (that  is,  by  drop- 


PRINCIPLE  26.      MERCURY.  205 

ping  very  small  globules  of  mercury  at  a  time  into 
boiling  nitric  acid)  and  then  pouring  into  a  solu- 
tion of  it,  a  solution  of  common  salt. 

Application.  The  first  method  exhibits  the 
principle  in  a  cheap  way.  But  a  very  different 
apparatus  is  adopted,  for  manufacturing  corrosive 
sublimate  in  a  large  way.  It  is  called  oxymuri- 
ate  of  mercury ;  but  as  it  consists  of  muriatic  acid 
combined  with  the  peroxid  of  mercury,  without 
any  oxy muriatic  acid,  it  is  properly  the  per- muri- 
ate of  mercury.  It  is  a  deadly  poison. 

Prop.  9.  Per- muriate  of  mercury  may  be  re- 
duced to  the  proto-muriate,  f  called  calomel )  by  be- 
ing rubbed  with  an  additional  portion  of  mercury, 
and  the  mixture  heated  to  the  state  of  sublimation. 

^Illustration.  Put  corrosive  sublimate  into 
Wedgewood's  mortar,  and  add  about  half  as  much 
by  weight  of  mercury.  (It  is  rather  more  safe  to 
add  about  an  eighth  more  mercury.)  Rub  them 
well  together,  until  there  is  no  appearance  of  mer- 
cury ;  it  having  all  become  a  powder.  Now  put 
it  into  a  florence  flask  and  sublime  it,  as  when 
making  the  corrosive  sublimate.  After  subliming 
once,  it  ought  to  be  scraped  out,  powdered  in  the, 
mortar  and  sublimed  again,  in  order  to  be  pure  and 
fit  for  use. 

Calomel  may  be  .made  by  pouring  a  solution  of 
common  salt  into  a  solution  of  nitrate  of  mercury 
made  cold.  It  is  best  to  add  a  little  muriatic  acid 
to  the  solution  of  common  salt. 

Application.  This  is  the  calomel  used  in  medi- 
cine. It  is  called  sub-muriate  of  mercury.  But 
as  it  consists  of  muriatic  acid  combined  with  the 
protoxid  of  mercury,  its  true  name,  according  to 

18 


206  CLASS   V*      METALS. 

correct  nomenclature,  is  proto-muriate  of  mercury. 
But  if  we  adopt  the  chlorine  doctrine,  the  subli- 
mate of  mercury  is  per  chloride  of  mercury,  and 
the  calomel  is  proto- chloride  of  mercury. 

This  method  of  preparing  those  salts  appears 
•wasteful ;  but  the  florence  flasks  can  be  had  for 
half  a  dollar  per  dozen,  and  there  is  no  other  me- 
thod within  my  knowledge  of  experimenting  so 
cheaply. 

Prop.  10.     Nitrate  of  mercury,  heated  with  al 
cohol,  may  be  formed  into  an  explosive,  or  fulmi- 
nating powder. 

^Illustration.  Make  the  nitrate  of  mercury  by 
heating  the  mercury  with  about  ten  times  as  much 
nitric  acid,  by  weight  \  which  will  be  in  a  liquid 
state.  After  it  is  cool,  pour  it  into  a  florence  flask 
with  about  one  fourth  more  alcohol.  Apply  a 
moderate  heat  until  effervescence  commences,  and 
no  longer.  After  effervescing  awhile,  and  pro- 
ducing fumes  on  the  surface,  a  powder  will  begin 
to  be  precipitated.  When  the  process  ceases,  pour 
off  the  liquid,  wash  the  powder  several  times  im- 
mediately in  pure  water,  and  then  dry  it  on  paper, 
It  must  be  dried  without  exposing  to  much  heat, 
or  it  will  explode  while  drying. 

Application.  By  striking  a  small  quantity  of 
this  powder  with  a  hammer  on  an  anvil,  it  will  ex- 
plode violently.  It  will  explode  by  compression 
under  the  feet  on  a  pavement,  if  well  dried.  It  is 
used  in  various  mixtures  for  small  fire- works,  &c. 
Though  it  is  not  so  dangerous  an  article  as  fulmi- 
nating silver,  it  ought  to  be  made  in  very  small 
quantities  only,  and  very  little  exploded  at  once. 
As  it  explains  no  principle,  which  cannot  as  well 
be  explained  by  experiments  of  less  danger,  it 


PRINCIPLE  27.      LEAD.  207 

will  generally  be  most  advisable  to  omit  it  in  the 
course  here  proposed. 

Prop.  11.  Corrosive  sublimate  may  be  reduced 
to  imperfect  calomel  by  animal  albumen. 

Illustration.  Beat  the  white  of  an  egg  in  water 
until  it  is  well  mixed  with  it.  Then  pour  it  into 
a  solution  of  corrosive  sublimate  ;  and  a  precipi- 
tate of  calomel  will  soon  appear. 

Application,  When  a  person  takes  corrosive 
sublimate  into  the  stomach  by  accident,  if  it  is  im- 
mediately discovered,  and  the  white  of  several 
eggs  is  swallowed,  the  poisonous  effect  will  pro- 
bably be  checked.  Milk  or  blood,  if  taken  in  the 
stomach  freely,  may  check  its  operation. 

Prop.  12.  Corrosive  sublimate,  the  per-murir 
ate  of  mercury,  may  be  detected  by  an  orange-yel- 
low precipitate,  made  with  lime-water, 

Illustration.  Dissolve  some  of  this  corrosive 
salt  in  water,  and  then  pour  into  it  some  lime  wa- 
ter ^immediately  an  orange-yellow  precipitate 
will  appear. 

Application.  Although  this  is  a  good  test, 
ihere  is  so  much  difficulty  in  obtaining  the  salt 
from  the  stomach  of  a  dead  body,  that  circumstan- 
tial evidence  ought  rather  to  be  relied  on,  than  the 
opinions  of  physicians  founded  on  such  an  exami- 
nation. It  is  more  soluble  than  arsenic  ;  conse- 
quently more  difficult  to  obtain  from  among  the 
liquid  contents  of  the  stomach. 

PRINCIPLE  27.     LEAD. 

Natural  History  and  general  Remarks. 
Lead  is  generally  found  mineralized  with  sul- 


208  CLASS    V.      METALS. 

phur,  in  an  oar  called  galena.  It  is  mncli  used 
in  the  arts  in  the  metallic  state.  It  is  alloyed  with 
tin,  forming  pewter.  Good  pewter  consists  of  one 
part  lead  to  four  of  tin  ;  but  most  of  the  pewter  of 
the  present  day  is  chiefly  lead.  Solder,  called 
plumber's  solder,  consists  of  equal  parts  of  lead 
and  tin  melted  together. 

Prop.  i.  Lead  receives  its  lowest  proportion 
of  oxygen  at  a  low  red  heat,  while  exposed  to  at- 
mospheric air  ;  also  from  the  decomposition  of  an 
acid,  with  which  it  is  combined  as  the  base  of  a  salt. 

^Illustration.  Melt  some  lead  in  a  ladle,  and 
scrape  off  the  pellicle  which  forms  on  its  sur- 
face several  times,  or  until  a  sufficient  quantity  is 
obtained.  Part  of  this  is  oxidated,  and  part  is  not. 
Now  put  this  into  the  ladle  by  itself  and  expose  it 
to  a  low  red  heat,  continually  stirring  it  with  a 
rod  until  it  becomes  of  a  yellow  colour.  This  is 
the  protoxid,  yellow  oxid,  or  massicot. 

Or  it  may  be  obtained  by  forming  the  nitrate  of 
lead  in  the  same  manner  as  .directed  for  forming 
the  nitrate  of  mercury,  and  then  by  heating  the 
salt  to  redness  in  a  ladle,  covered  over  pretty  close- 
ly 5  the  acid  is  driven  out,  leaving  the  protoxid  of 
lead. 

Application.  This  is  the  massicot  used  in  the 
arts.  It  is  also  an  useful  powder  for  setting  a  fine 
edge  to  razors,  for  polishing  burnishers,  &c. 

Prop.  2.  The  protoxid  of  lead  will  become  the 
deutoxid,  by  exposing  it  to  atmospheric  air  in  a 
strong  heat,  not  quite  bringing  the  powder  to  a 
state  of  fusion. 

^Illustration.  Put  some  massicot  into  a  ladle, 
and  cover  it  over  loosely  with  an  earthen  or  iron 


PRINCIPLE   27.      LEAD.  209 

plate,  and  raise  the  heat.  Raise  up  one  end  of 
the  plate  and  stir  it  often,  until  it  becomes  of  a 
bright  red.  Care  must  be  taken  not  to  raise  the 
heat  so  high  as  to  drive  off  the  previously  acquir- 
ed oxygen,  and  thereby  bring  it  again  to  the  state 
of  pure  melted  lead.  It  is,  in  fact,  difficult  to  per- 
form this  operation  with  small  quantities. 

Application.  This  is  red  lead  or  minium,  used 
by  painters.  On  this  principle,  though  with  very 
different  apparatus,  red  lead  is  manufactured  for 
the  shops.  But  the  red  lead  of  the  shops  is  gen- 
erally very  impure.  It  often  contains  red  ochre, 
silex,  alu mine,  muriate  of  lead,  sulphate  of  lead, 
.&c. 

Prop.  3.  Minium  becomes  litharge  by  heating 
a  considerable  time  in  as  high  a  heat  as  it  can  bear, 
without  parting  with  its  oxygen. 

^Illustration.  Put  some  red  lead  into  a  ladle, 
and  heat  it  until  it  is  partly  melted,  so  that  it  be- 
gins to  be  agglutinated  in  a  kind  of  scales. 

Application.  This  is  the  semi-vitreous  oxid  of 
lead,  usually  called  litharge.  It  is  not  so  bright 
a  red,  but  is  a  more  durable  colour. 

Prop.  4.  By  raising  the  heat  very  high,  oxid 
of  lead  gives  its  oxygen  wholly  off,  and  becomes 
pure  had  again. 

Illustration.  Put  some  red  lead  into  a  cruci- 
ble and  raise  the  heat  as  high  as  the  white  heat  of 
iron  ;  and  pure  metallic  lead  will  be  found  in  the 
crucible. 

Application.  This  last  experiment  is  an  illus- 
tration of  the  distinctive  character  of  this  section* 

16* 


CLASS  V.      METALS. 

Prop.  5.  Red  oxid  of  lead  will  decompose  mu 
riate  of  soda,  with  heat,  and  form  the  patent  yet 
low. 

Illustration.  Pulverize  common  table  salt  very 
finely  and  put  it  into  Wedgewood's  mortar.  Put 
in  with  it  twice  as  much  finely  pulverized  red  lead 
after  it  had  been  heated  until  it  become  yellowish, 
or  the  same  quantity  of  litharge.  Rub  them  well 
together  first ;  then  add  water,  a  very  little  at  a 
time,  and  continue  rubbing  until  a  paste  is  formed. 
Muriate  of  lead  will  now  be  formed,  and  the  soda 
will  be  disengaged.  Pour  in  a  large  quantity  of 
"Water  and  wash  it  several  times.  The  soda  will 
wash  out  and  leave  a  white  mass.  Dry  this  mass 
and  then  melt  it  in  a  crucible ;  and  a  beautiful  sub- 
stance will  be  formed,  called  patent  yellow. 

Application.  The  patent  yellow  is  one  of  the 
most  durable  pigments,  and  may  be  made  very 
good  in  this  way. 

Prop.  6.  Carbonate  of  lead,  called  white  lead, 
28  formed  by  double  decomposition  on  mixing  ni- 
trate of  lead  and  pearlash. 

Illustration.  Make  nitrate  of  lead  as  before  di- 
rected, and  dissolve  it  in  water  in  a  wine-glass. 
Pour  into  it  a  solution  of  pearlash,  and  a  white 
insoluble  precipitate  will  fall  down.  Let  the  li- 
quid be  poured  off,  and  the  powder  washed  sev- 
eral times. 

Application.  This  is  the  white  lead  of  painters 
in  its  purest  state.  It  is  generally  made  in  the 
large  way  by  applying  the  vapour  of  vinegar  to 
sheet  lead.  It  will  of  course  contain  some  acetate 
of  lead  and  other  impurities. 

Prop.  7.     White  lead,  carbonate  of  lead,  dis 
solved  in  vinegar,  forms  sugw  of 


PRINCIPLE   28.      NICKEL.  211 

^Illustration.  Put  some  white  lead  into  a  for- 
cnce  flask.  Put  in  about  ten  times  as  much  good 
sharp  vinegar,  (distilled  vinegar  is  best.)  Shake 
it  up  several  times  and  let  it  stand  until  the  vine- 
gar tastes  sweet.  Add  more  vinegar  and  continue 
adding  by  littles,  until  it  will  remain  sour.  Evap- 
orate and  crystallize  in  the  usual  way. 

Application.  This  is  the  acetate  of  lead,  or  su- 
gar of  lead,  used  in  medicine.  It  is  called  sugar 
of  lead  on  account  of  its  sweet  taste. 

Prop.  8.  Lead  is  precipitated  from  the  state  of 
a  salt  in  the  metallic  state  by  metallic  %inc. 

Illustration.  Dissolve  sugar  of  lead  in  thirty 
or  forty  times  its  weight  of  water.  Fill  a  decan- 
ter with  this  solution.  Suspend  a  small  clean 
bright  piece  of  zinc  in  the  liquid  by  a  thread, 
which  is  held  by  being  compressed  by  the  side  of 
the  stopper.  Set  the  decanter  in  a  conspicuous 
place  in  the  class-room  where  it  may  remain  a  day 
or  two  undisturbed.  The  acetate  of  lead  will  be 
decomposed.  The  lead  will  cover  the  zinc  with 
leaves  shooting  out  in  a  curious  manner,  while  the 
sour  taste  of  the  vinegar  is  partly  restored. 

Application.  Zinc  having  a  stronger  affinity 
for  oxygen  than  lead,  it  takes  so  much  from  it, 
that  it  cannot  hold  the  vinegar  any  longer  in  com* 
bination  with  it. 

PRINCIPLE  28.     NICKEL. 
Natural  History  and  general  Remarks* 

Nickel  is  generally  obtained  from  the  sulphu- 
ret.  It  is  found  alloyed  with  iron  in  meteoric 
stones.  Its  colour,  when  pure,  is  between  those 


212  CLASS   V.      METALS. 

of  silvrer  and  tin  5  but  it  generally  exhibits  a  pale 
Hesh  coloured  tinge,  tire  says  it  is  magnetic : 
Accum  is  just  as  positive  that  it  is  not  magnetic. 
Others  differ  in  opinion  on  this  subject.  Accum, 
Chenevix  and  others  say,  it  is  the  iron  which  is 
alloyed  with  the  nickel,  that  attracts  the  magnet. 
It  is  a  rare  metal. 

Nickel  forms  a  salt  with  nitric  acid,  which  may 
be  made  to  exhibit  several  colours. 

Illustration.  Put  an  excess  of  nickel  into  a 
strong  solution  of  nitric  acid,  and  let  it  remain  un- 
til the  acid  is  saturated.  The  liquid  will  be  the 
green  nitrate  of  nickel  in  solution.  Pour  in  liquid 
ammonia  in  excess  and  a  blue  precipitate  is  form- 
ed ;  and  this  will  become  reddish  purple  in  a  few 
hours,  which  may  be  brought  back  to  a  green  co- 
lour by  an  acid* 

Application.  Nickel  is  not  much  used,  except- 
ing as  a  subject  of  philosophic  speculation  in  re- 
gard to  its  magnetism,  its  presence  in  all  meteoric 
stones,  and  its  varying  hues  as  the  basis  of  a  salt, 


213 

OEGANIC  SUBSTANCES. 

General  Remarks. 

Under  organic  substances  are  included  the  sub- 
jects of  the  vegetable  and  animal  kingdoms.  The 
ultimate  elements,  constituting  all  vegetable  and 
animal  substances,  have  been  described,  and  their 
chief  properties  illustrated  by  experiments,  in  the 
preceding  part  of  this  work.  But  when  those 
simple  substances  are  arranged  according  to  the 
laws  of  organization,  and  endowed  with  the  living 
principle,  phenomena  are  induced  which  elude  the 
researches  of  the  chemist. 

The  constituents  of  vegetable  and  animal  mat- 
ter are  properly  divided  into  proximate  and  ulti- 
mate elements.  The  proximate  elements  are  those, 
compounds  into  which  animal  and  vegetable  mat- 
ter may  be  resolved,  and  still  retain  properties 
most  nearly  resembling  these  organic  substances, 
before  they  were  subjected  to  the  process  of  de- 
composition. Such  asjesin,  starch,  gum,  glue, 
albumen,  oil,  &c.  The  ultimate  elements  are  the 
simple  substances  into  which  they  may  be  resolv- 
ed, by  a  thorough  analysis.  Such  as  oxygen,  car 
bon,  &c. 

Much  progress  has  been  made  in  this  depart 
inent  of  chemistry  within  a  few  years.  But  the 
complex  nature  of  organic  matter  presents  many 
difficulties,  and  the  analyses  are  very  slow  and  te- 
dious. By  following  the  directions  given  by  such 
extensive  and  learned  works  as  those  of  Thomp- 
son, Ure,  M'Neven's  Brand,  Grorham,  Silliman's 
Henry,  &c.  we  may  succeed  in  repeating  the  ex- 
periments, necessary  for  demonstrating  the  truth 
of  those  principles,  adopted  by  the  great  philoso- 


214  ORGANIC    SUBSTANCES. 

pliers  of  the  age.  But  such  a  course  of  experi- 
ments would  require  the  labour  of  many  months, 
or  perhaps  of  years. 

Having  become  practically  acquainted  with  the 
most  important  properties  of  all  the  elementary 
constituents  of  animal  and  vegetable  matter,  we 
are  now  prepared  to  understand  the  descriptions 
given  us  by  those,  who  have  patiently  and  labori- 
ously investigated  them.  We  must  therefore  con- 
tent ourselves  with  the  history  of  their  labours^ 
and  rely  upon  the  truth  of  their  experiments  ;  as 
we  do  upon  the  astronomical  calculations  of  New- 
ton, Le  Lande,  Herschel  and  others. 

While  animals  and  vegetables  are  in  the  living 
state,  that  undescribed  something,  called  the  liv- 
ing principle,  renders  their  operations  intricate 
and  complicated.  Two  active  principles,  the  liv- 
ing principle,  and  ihe  principle  of  chemical  affini- 
ty) are  perpetually  at  war  with  each  other.  The 
latter  is  disposed  to  derange  the  organic  structure, 
and  to  form  new  chemical  compounds.  But  the 
former  is  the  more  powerful,  and  resists  the  inces- 
sant attacks  of  the  latter.  Chemical  affinity  is  ex- 
erting its  energies  every  moment  of  our  lives  to 
convert  our  bodies  into  the  most  odious  gases,  and 
inorganic  liquids  and  solids.  But  the  living  prin- 
ciple maintains  its  empire  for  a  few  years.  A( 
last  yielding  to  the  unabating  efforts  of  chemical 
affinity,  the  most  beautiful  face  loses  its  youthful 
glow,  and  the  speaking  eye  loses  its  brilliancy. 
They  are  given  over  to  form  the  constituent  ele- 
ments of  sulphuretted  hydrogen,  carburetted  hy- 
drogen, ammonia,  carbonic  acid,  and  other  inor- 
ganic substances.  What  now  constitutes  the  sym- 
metry and  all  the  fascinations  of  beauty,  may  be 


VEGETABLE  SUBSTANCES.        215 

converted  into  the  various  gases;  which,  after 
floating  a  while  at  the  pleasure  of  the  winds,  are 
absorbed  by  the  earth,  and  re-appear  in  the  form 
of  a  rose,  an  ear  of  corn,  or  the  deadly  nightshade. 
The  well  known  fact,  that  the  living  principle  is 
at  variance  with  the  laws  of  matter,  demonstrates 
conclusively  that  every  living  being,  whether  ani- 
mal or  vegetable,  is  essentially  composed  of  mat- 
ter, and  of  a  substance  distinct  from  matter.  The 
existence  of  one  substance  being  proved,  with 
properties  not  only  distinct  from  matter  but  direct- 
ly opposed  to  the  laws  of  matter,  completely  over- 
throws every  argument  of  the  materialist.  For  af- 
ter the  existence  of  one  immaterial  substance  is 
proved  by  sensible  properties,  the  existence  of  an- 
other may  be  reasonably  inferred  from  its  proper- 
ties also.  Therefore  the  faculty  of  thinking  points 
to  an  intellectual  substance  ;  though  its  existence 
has  not  been  demonstrated  by  actual  experiment, 
like  that  of  the  living  principle. 

VEGETABLE  SUBSTANCES. 

ULTIMATE  ELEMENTS. 

Vegetable  matter  is  essentially  composed  of  car- 
bon) oxygen  and  hydrogen. 

The  cruciform  family  of  plants,  such  as  cabbage, 
mustard,  radishes,  &c.  contain  a  little  nitrogen. 
In  some  few  plants,  sulphur  has  been  detected. 
Potash,  lime,  soda,  magnesia,  and  silex,  have  been 
found  in  plants. 

When  vegetable  matter  is  heated  in  a  retort  to 
that  degree  which  is  called  destructive  distillation, 
the  constituent  elements  assume  new  arrange* 


216  VEGETABLE    SUBSTANCES. 

ments;  and  carbonic  acid,  carbonic  oxid,carbu~ 
retted  hydrogen,  empyneumatic  oil,  water,  8£c. 
come  over,  leaving  charcoal,  and  generally  some 
earths  and  salts,  in  the  retort. 

After  these  products  are  separated,  each  is  an- 
alyzed. From  the  result  of  these  analyses,  the 
proportions  of  carbon,  oxygen  and  hydrogen  are 
ascertained.  Or  if  we  rely  upon  the  analyses  of 
these  products,  which  have  been  made  by  chem- 
ists, we  have  only  to  ascertain  the  proportions  of 
these  products  to  be  enabled  to  calculate  the  quan 
tity  of  the  ultimate  elements  contained  in  any  ve- 
getable substance  under  examination. 

PROXIMATE  ELEMENTS* 

These  elements  may  be  distributed  into  Jive  di- 
visions by  a  trial  of  their  solubility. 

Illustration.  Dissolve,  or  attempt  to  dissolve, 
one  or  more  of  the  elements  of  each  division ;  if 
the  solution  is  made,  precipitate  it  by  adding  an 
excess  of  a  substance  which  is  not  its  solvent. 

Application.  When  any  of  the  proximate  ele- 
ments, enumerated  below,  are  to  be  used,  let  them 
be  brought  to  the  liquid  state,  or  precipitated,  as 
their  application  may  require. 

First  Division. 

Proximate  elements,  which  are  soluble  in  cold 
water. 

Acids,  sugar,  gum,  jelly,  colouring  principle^ 
bitter  principle,  nicotin,  extractive  matter,  emetin, 

Second  Division. 

Proximate  elements,  which  are  insoluble  in  cold 
water,  but  partially  soluble  in  hot  water. 


VEGETABLE  SUBSTANCES.        217 

Morphia,  cerasin,  starch,  indigo,  glutin,  polle 
mn,  fibrin. 

Third  Division. 

Proximate  elements  which  are  insoluble  in  wa- 
ter and  melt  and  burn  when  heated.  Most  oJ" 
them  are  soluble  in  alcohol. 

Fixed   oil,  wax,  volatile  oil,  camphor,  resin, 
guaiacum,  balsam,  gum-resin,  caoutchouc,  bitu 
men. 

Fourth  Division. 

Proximate  elements,  which  are  not  soluble  ei- 
ther in  water,  alcohol,  or  ether ;  having  a  fibrous 
or  woody  texture. 

Cotton,  cork,  pitch,  wood,  fungus. 

fifth  Division. 

Extraneous  substances  sometimes  found  in  vc 
getables. 

Mineral  acids,  alkalies,  earths,  metals. 

DISTINCTIVE   CHARACTERS. 

First  Division. 
JLcids. 

Acetic  acid  is  distinguished  by  the  well  known 
odour  of  vinegar.  It  is  generally  produced  by  fer- 
mentation from  wine,  cider,  &c.  But  it  is  found 
ready  made  in  the  fruit  of  rhus  typhinum  and  somo 
other  plants. 

Oxalic  acid  decomposes  all  salts  of  lime.  It  is 
found  in  the  oxalis  stricta,  and  other  plants.  Heat 
destroys  it. 

Tartaric  acid  forms  the  common  tartar  if  a  little 
potash  is  dropped  cautiously  into  a  solution  of  itv 

19 


218        VEGETABLE  SUBSTANCES. 

It  is  found  in  rhus  typhinum,  oxycoccus,  &c.  But 
is  generally  obtained  from  the  lees  of  wine.  Heat 
destroys  it. 

Citric  acid  does  not  form  tartar  with  potash.  It 
is  found  in  the  juice  of  oranges,  lemons,  in  oxy- 
coccus,  &c.  Heat  destroys  it 

Malic  acid  does  not  form  tartar  with  potash, 
and  it  forms  a  salt  with  lime,  which  is  soluble  in 
water  and  decomposed  by  citric  acid.  It  is  found 
in  green  sour  apples,  the  barberry,  &c. 

Benzole  acid  is  volatile  in  moderate  heat  and  is 
aromatic.  It  is  found  in  the  styrax  tree  chiefly  5 
but  it  is  also  found  in  the  laurus  benzoin,  origan- 
um majorana,  &c. 

Prussic  acid  forms  the  prussian  blue  when  pour- 
ed into  a  solution  of  copperas.  It  is  found  in 
peach  meats  and  blossoms,  &c.  It  is  called  the 
hydrocyanic  acid  by  some  chemists.  See  this  ar- 
ticle under  animal  substances,  from  which  it  is  ob- 
tained for  use  in  the  arts. 

Kinic  acid,  on  burning  coals,  froths,  melts  and 
turns  black,  and  finally  is  exhaled  in  acid  vapour. 
It  does  not  precipitate  nitrate  of  mercury  or  silver. 
It  is  obtained  from  Peruvian  bark. 

Gallic  acid  produces  a  black  colour  with  the 
oxid  of  iron.  It  is  found  chiefly  in  most  species 
of  oak  ;  but  many  other  trees  contain  it  also. 

Tannin  unites  with  a  solution  of  animal  jelly 
(rather  prefers  the  isinglass)  and  forms  a  dense 
precipitate.  It  is  found  is  every  species  of  oak, 
and  in  the  pinus  canadensis.  It  is  most  abundant 
in  the  bark  of  trees. 

Its  use  in  the  manufacture  of  leather  depends 
on  its  affinity  for  animal  gelatin. 

Sugar  dissolves  rapidly  in  water,  more  espe- 
cially if  heated,  and  dissolves  slowly  in  alcohol. 


VEGETABLE  SUBSTANCES.        219 

It  is  combustible,  and,  when  mixed  witb  oxy muri- 
ate of  potash,  if  a  little  sulphuric  acid  be  applied, 
it  burns  spontaneously. 

Sugar  preserves  fruits  from  putrefaction,  but 
tends  to  promote  the  decay  of  human  teeth.  It  is 
nutritive  as  a  diet,  and  assimulates  kindly  with 
human  fluids. 

It  is  chiefly  obtained  from  the  common  sugar 
cane  and  the  sugar  maple.  It  may  be  obtained 
from  the  stalks  of  indian  corn,  pumpkins,  beets, 
&c. 

Sugar  is  purified  by  boiling  with  blood  of  cattle, 
which  brings  to  the  surface  all  impurities.  By 
heating  sugar  with  nitric  acid,  oxalic  acid  is  form 
ed.  Alkalies  in  solution  mixed  with  sugar  in  so- 
lution, destroy  its  sweetness  ;  which  is  restored 
by  a  due  portion  of  acid.  Consists  of  51.3  oxy- 
gen, 6.8  hydrogen,  41.9  carbon. 

Gum  is  highly  soluble  in  water,  forming  a  mu- 
cilage ;  but  is  insoluble  in  alcohol.  Gum  is  con- 
verted into  citric  acid,  by  chlorine.  It  oozes  from 
wounds  in  cherry  trees,  peach  trees,  &c.  Some 
of  the  chief  gums  of  commerce  are  gum  arable  and 
gum  Senegal. 

Jelly  is  scarcely  soluble  in  cold  water.  It  readi- 
ly assumes  a  kind  of  half  coagulated  tremulous 
state.  It  exists  in  currants,  gooseberries  and  many- 
other  fruits. 

Colouring  principle,  is  found  in  many  of  the 
proximate  elements  of  vegetables.  The  logwood, 
nickaragua,  madder,  &c.  of  the  shops  are  well 
known.  We  find  it  abundant  in  the  common  but- 
ternut tree,  the  walnut  tree,  &c.  Most  vegetable 
colouring  materials  require  a  mordant  to  fix  the 
colouring  in  the  stuffs  5  some  of  which  fix  the  col- 


320        VEGETABLE  SUBSTANCES. 

our  without  change,  others  produce  a  change  in 
the  colour. 

Bitter  principle  is  known  by  the  taste.     It  is 
generally  very  soluble  in  water  or  alcohol.     It  is 
generally  precipitated  by  nitrate  of  silver  and  by 
acetate  of  lead.     It  is  found  in  numerous  vegeta 
foles. 

Extractive  principle  is  chiefly  applied  to  all 
substances  which  are  extracted  from  plants  by  the 
aid  of  water  and  remain  in  the  state  of  a  dry  mass 
after  the  water  is  evaporated.  Therefore  sugar,, 
liquorice,  gum,  jelly,  &c.  are  included  in  it.  But 
Thompson  proposes  a  more  narrow  and  more  de 
Unite  limit  to  the  term. 

Emitin  is  supposed  to  be  a  peculiar  principle 
iin  ipecacuanha  and  most  other  plants,  which  cause 
the  stomach  to  throw  up  its  contents. 

Second  Division. 

Morphia,  a  principle  contained  in  the  poppy 
and  some  other  plants,  which  induces  sleep. 

Cerasin  is  a  principle  which  has  been  confound- 
ed  with  the  gums.  But  it*  differs  from  gum  in 
swelling  and  becoming  transparent  in  cold  water, 
without  actually  becoming  dissolved  until  the  wa 
ter  is  heated.  The  gum  tragacanth  is  pure  cera- 
sin. 

Starch9  though  it  does  not  dissolve  in  cold  wa- 
ter, it  falls  into  powder.  With  boiling  water  it 
forms  a  kind  of  jelly.  It  does  not  even  fall  into 
powder  in  alcohol.  When  dried  it  becomes  a 
white  brittle  mass. 

Starch  may  be  washed  from  its  connection  with 
gluten  in  wheat  flour  in  cold  water,  from  which  it 
will  soon  settle  in  the  state  of  powder.  It  is  ob- 
tained from  potatoes  also  and  numerous  other 
vegetables. 


VEGETABLE  SUBSTANCES.        221 

Gluten  forms  with  water  a  soft  tenaceoiis  duc- 
tile paste.  It  may  be  obtained  almost  pure  by 
making  bakers'  dough  in  the  usual  way,  and  then 
washing  it  in  cold  water,  until  the  water  comes  off 
clear.  The  starch  being  extricated  in  this  man- 
ner, the  remainder  will  be  nearly  pure  gluten. 
Gluten,  like  animal  gelatin,  is  precipitated  from 
its  solution  in  water  by  an  infusion  of  galls. 

Indigo  is  scarcely  soluble  in  hot  water,  but  dis- 
solves in  alkaline  leys  and  becomes  reddish.  The 
pure  colouring  matter  of  indigo  does  not  exceed  47 
percent.'  The  other  constituents  are  separated 
by  1st  water,  2d  alcohol,  3d  muriatic  acid.  These 
several  solutions  being  poured  off  and  the  sedi- 
ment washed  in  succession,  the  last  sediment  is 
the  pure  colouring  matter,  and  burns  with  a  purple 
smoke. 

Fibrin,  which  will  be  mentioned  under  animal 
matter,  has  been  detected  in  the  juice  of  the  papaw 
tree  in  Peru.  Nothing  short  of  the  authority  of 
Yauqueliri  could  commend  our  belief  in  such  a  re- 
markable case. 

Third  Division* 

Wax. — Vegetable  wax  is  found  on  the  surface 
of  the  fruit  of  the  bay-berry,  (Myrica  cerifera.J 
JBees-wax  is  also  a  very  perfect  vegetable  wax, 
when  purified  and  in  the  state  of  white  wax.  it 
is  soluble  in  heated  fixed  oils,  when  it  forms  the 
cerates  of  physicians.  Some  of  the  volatile  oils 
dissolve  it  also.  It  is  soluble  in  potash  and  soda, 
forming  a  soap-like  compound.  It  is  not  much 
affected  by  acids  ;  therefore  it  is  useful  in  etching? 
luting,  &c. 

19* 


,222  VEGETABLE   SUBSTANCES. 

Fixed  Oils.  Vegetable  fixed  oil  is  pressed 
from  the  flax  seed  in  large  quantities  ;  and  is  much 
used  by  painters.  Castor  oil,  which  is  pressed 
from  the  castor  bean  (Ricinus  communis,)  is  used 
in  medicine.  Fixed  vegetable  oil  may  be  pressed 
from  the  fruit  of  the  walnut,  butternut,  &c.  Olive 
oil  is  also  an  important  fixed  oil.  A  fixed  oil  may 
be  separated  into  the  concrete  pwt9-fstearinej  and 
the  fluid  part  (daine.J  And  they  are  more  or  less 
inclined  to  retain  the  liquid  state,  according  to  the 
proportion  of  elaine  contained  in  them. 

Some  oils  readily  become  hard  and  resinous  on 
exposure.  These  are  called  drying  oils.  They 
are  used  in  the  manufacture  of  printer's  ink.  It  is 
pretty  highly  heated,  set  on  fire  and  burned  about 
half  an  hour,  then  extinguished  and  boiled  down 
until  it  is  of  a  suitable  consistency.  Afterwards 
it  is  mixed  with  some  spirits  of  turpentine  and 
lamp  black.  Nut  oil  is  preferred  for  printer's  ink ; 
but  linseed  oil  is  often  used. 

Fixed  vegetable  oils  combine  with  the  alkalies 
and  form  soap.  The  best  hard  soap  made  is  of 
olive  oil  and  soda. 

Volatile  Oils.  These  oils  are  very  numerous. 
They  are  distinguished  from  fixed  oils  by  being 
converted  into  a  state  of  vapour  by  heat ;  where- 
as fixed  oils  cannot  be  evaporized  or  volatilized 
without  combustion,  and,  of  course,  decomposi- 
tion. Some  of  the  most  common  volatile  oils  are, 
spirits  of  turpentine,  oil  of  lemons,  juniper,  rose- 
mary, tansy,  wintergreen,  mint,  (called  pepper- 
mint essence,);  pennyroyal,  fennel,  cloves,  cinna- 
mon, aniseed,  dill,  &c.  They  are  highly  soluble 
in  alcohol,  but  hardly  soluble  in  water,  They 
are  mostly  obtained  by  steeping  vegetables  in  wa* 


VEGETABLE  SUBSTANCES.        223 

ter,  and  then  distilling  over  in  common  stills, 
They  are  generally  called  essences,  because  they 
contain  the  essence  of  the  sensible  qualities  of  the 
vegetable. 

The  volatile  oils  become  thick  and  somewhat 
resinous  by  the  absorption  of  oxygen  on  long  ex- 
posure to  air.  It  is  probable  that  volatile  oils  be- 
come indurated  and  give  strength  and  durability 
to  the  woody  fibre  by  drying.  For  when  timber 
is  water- seasoned,  as  it  is  called.,  (that  is  soaked 
in  water  awhile  and  then  dried  to  prevent  its 
shrinking,)  it  is  more  easily  broken  and  decays 
sooner.  Wood  is  found  to  be  less  valuable  as 
fuel,  which  is  cut  down  while  green  and  exposed 
to  rains.  In  both  cases  the  volatile  oil  is  extract- 
ed more  or  less  by  water.  It  is  therefore  better 
for  fuel  or  timber  when  it  is  cut  down  in  a  green 
thrifty  state  and  dried  or  seasoned  under  a  shelter. 
If  a  volatile  oil  is  adulterated  by  a  fixed  oil,  it 
may  be  detected  by  rubbing  a  little  of  it  on  paper, 
and  holding  it  near  the  fire.  The  volatile  oil  will 
evaporate  and  leave  a  greasy  spot  on  the  paper, 
which  is  made  by  the  fixed  oil.  The  essence- 
pedlers  generally  purchase  a  small  quantity  of  the 
volatile  oils,  and  then  adulterate  largely  with  alco- 
hol. This  is  a  very  common  fraud,  and  ought  to 
be  detected  and  exposed,  'which  may  be  done  by 
pouring  a  few  drops  into  a  wine-glass  of  water, 
The  pure  essence  will  float  on  the  water,  and 
scarcely  mix  with  it  at  all.  But  if  it  is  adulterat- 
ed with  alcohol,  it  will  mix  with  the  water,  and  a 
change  in  colour,  &c.  will  instantly  appear. 

Camphor.  This  substance  is  obtained  from  the 
camphor  tree  of  Japan,  (Laurw  camphora.J— 
This  is  a  species  of  the  same  genus  with  theeassa- 


224        VEGETABLE  SUBSTANCES, 

\ 

fras  and  spice-bush  of  our  country.  And  the 
camphor  has  many  properties  in  common  with  the 
volatile  oil  of  sassafras  and  other  vegetables.  It 
is  soluble  in  alcohol  and  hardly  soluble  in  water  5 
it  dissolves  in  both  the  fixed  and  volatile  oils. 

Camphor  may  be  made  artificially.  At  least  a 
substance  is  deposited  very  similar  to  camphor, 
by  passing  a  current  of  muriatic  acid  gas  through 
spirits  of  turpentine. 

Resins.     The  juice  which  exudes  from  the 

white  pine,  and  several  other  species  of  the  genus 

pinus,  consists  of  the  resin  and  the  volatile  oil, 

called  spirits  of  turpentine.     By  distilling  over 

Uhe  latter,  the  former  remains  pretty  pure. 

Pure  resin  is  insoluble  in  water,  soluble  in  al- 
cohol and  the  alkalies,  and  almost  devoid  of  taste 
or  smell.  Those  which  do  give  off  an  odour,  are 
combined  with  volatile  oil ;  and*are  generally  de- 
nominatedbalsams.  .Besides  those  resins  which 
come  under  the  general  denomination  of  pitch,  are 
the  guaiacum,  copal,  mastich  and  others  ;  the  two 
last  of  which  are  hardly  soluble  in  alcohol.  There 
are  several  hard  resins,  called  lac,  which  are  de- 
posited by  an  insect  in  the  East  Indies,  on  twigs  of 
trees,  &c.  the  most  common  of  these  is  called  shell- 
lac. 

There  are  compounds  of  gum  arid  resin,  called 
gum-resins.  Gramboge  and  assafoetida  are  of  this 
kind.  As  gum  is  soluble  in  water  and  resin  in 
alcohol,  it  requires  both  for  their  solution.  Jhn- 
ber  is  placed  under  resins  ;  but  it  is  hardly  solu- 
ble in  alcohol  or  in  the  alkalies. 

Caoutchouc.  This  substance  is  generally  called 
india  rubber.  It  is  manufactured  by  drying  the 
juice  of  an  East  India  plant,  called  the  Urceok 
elastica,  according  to  Sprengel  and  Roxburgh „ 


VEGETABLE  SUBSTANCES.        225 

It  is  also  obtained  from  a  South -American  plant, 
called  Siphonia  elastica  by  Linneus  ;  Lamarck 
calls  it  Hevea  guiauensis.  Both  of  these  plants 
belong  to  the  same  natural  order  with  our  common 
milk- weed  (Asclepias  syriacus,J  and  the  juice  of 
the  milk-weed,  when  dried,  resembles  the  india 
rubber.  It  is  very  elastic  and  inflammable.  It 
contains  nitrogen.  It  is  insoluble  in  water  ;  but 
may  be  softened  and  rendered  very  adhesive  in 
hot  water,  so  as  to  be  made  into  flexible  tubes  by 
winding  slips  of  it  spirally  around  small  cylinders 
and  uniting  the  edges. 

Bitumen.  This  substance  partakes  something 
of  the  nature  of  oils  and  resin.  When  pure,  it  is 
a  limpid  liquid,  and  is  then  called  naphtha.  It 
consists  of  about  87  per  cent  carbon,  and  13  per 
cent  hydrogen.  As  it  contains  no  oxygen,  the  in- 
flammable bases  of  potash,  &c.  are  kept  in  it. — 
When  in  the  state  of  a  brownish  iridescent  liquid, 
as  it  is  seen  floating  on  stagnant  waters,  it  is  call- 
ed petroleum.  When  in  the  solid  state,  as  it  is 
found  in  Trinidad,  and  on  the  shores  of  Luke  As- 
phaltides,  it  is  called  asphalt. 

PRODUCTS  OF  FERMENTATION. 

Some  vegetable  solutions  will  undergo  spontane 
ous  changes,  whereby  alcohol  or  vinegar  is  produc- 
ed ;  during  this  process  carbonic  acid  %as  is  evolv- 
ed. 

Illustration.  Put  some  sugar  into  a  florencc 
flask,  and  dissolve  it  with  about  five  times  as 
much  warm  water,  and  add  a  little  yeast.  Set  it 
where  it  will  continue  to  be  warm,  but  not  hot. 
Let  one  end  of  a  bent  lead  or  glass  tube  be  fitted 
into  the  flask  by  perforating  a  sound  cork,  and  let 


226  VEGETABLE  SUBSTANCES. 

the  other  end  pass  under  the  moveable  shelf  of  the 
cistern.  After  standing  awhile,  a  gas  will  begin 
to  come  over. — As  soon  as  the  atmospheric  air  has 
passed  out,  begin  to  collect  the  gas.  On  testing 
it  with  lime  water,  it  will  be  found  to  be  carbonic 
acid  gas. 

Application.  From  this  experiment  it  appears, 
that  sugar  alone  is  sufficient  to  produce  fermenta- 
tion with  water,  when  started  with  yeast.  It  is 
found  that  sugar  is  essential  by  many  trials.  This 
is  the  same  gas  which  issues  from  cider,  beer,  &c. 
when  fermenting — it  is  also  produced  in  dough 
when  rising. 

The  intoxicating  substance  called  alcohol,  is 
produced  during  fermentation.  Alcohol  being 
converted  into  vapour  with  less  heat  than  water, 
it  may  be  distilled  over  by  a  due  degree  of  heat. 
Thus  rum,  brandy,  gin,  cider-brandy,  &c.  are  ob- 
tained. 

Cider  is  sometimes  boiled  down  for  family  use  ; 
as  for  making  apple  preserves,  &c.  This  should 
always  be  done  before  fermentation  commences; 
because  alcohol  will  then  be  formed,  which  will 
be  driven  off  and  wasted  by  evaporation,  while 
boiling  down  the  cider. 

The  ardent  spirits  of  commerce  consist  of  alco- 
hol combined  with  water,  and  some  other  adulterat- 
ing substances,  giving  each  kind  its  peculiar  fla- 
vour ;  from  either  of  which  pure  alcohol  may  be 
obtained  by  re- distillation,  and  the  absorbing  power 
of  potash. 

Illustration.  Fill  a  pint  retort  half  full  of  com- 
mon proof  whiskey.  Fit  the  beak  to  a  receiver 
and  surround  the  neck  with  beeswax  where  it  en- 
ters the  receiver  5  so  that  it*  water  is  applied  to 


VEGETABLE  SUBSTANCES.        227 

the  neck  of  the  retort  it  cannot  run  into  the  receiv- 
er. Let  the  receiver  be  immersed  in  cold  water, 
or  surrounded  with  snow.  Set  the  retort  into  the 
lead  pot  over  coals  in  the  usual  way,  and  raise  the 
heat  by  the  hand  bellows.  Set  the  lead  pot  so 
near  the  cistern,  that  cold  water  may  be  poured 
on  the  neck  of  the  retort  and  be  renewed  in  the 
vessel  where  the  receiver  is  immersed,  without 
wetting  the  room  Alcohol  will  rise  up  in  vapour 
and  be  condensed  in  the  neck  of  the  retort,  and 
run  down  into  the  receiver.  After  the  measure 
of  the  alcohol  in  the  receiver  about  equals  the 
measure  of  what  remains  in  the  retort,  stop  the 
process. 

Put  into  a  tumbler  a  quantity  of  pearlash,  about 
equal  in  weight  to  one  fourth  of  the  alcohol  dis- 
tilled over,  which  had  been  made  as  dry  as  pos- 
sible on  a  plate  exposed  to  a  little  heat,  let  the 
pearlash  be  warm  as  can  be  borne  by  the  hand 
when  put  into  the  tumbler,  and  pour  the  alcohol 
upon  it.  Stir  it  up  and  keep  the  alcohol  in  the 
tumbler  with  it,  about  half  an  hour.  Now  let  it 
settle  and  pour  out  the  alcohol  for  use. 

Application.  By  this  method  very  pure  alco- 
hol may  be  obtained.  On  the  same  principle, 
with  large  retorts  and  receivers,  alcohol  may  be 
obtained  for  the  use  of  the  physicians  and  the  ar- 
tist. If  carefully  distilled  and  well  prepared,  it 
will  be  so  inflammable  that  if  it  be  poured  upon 
an  earthen  plate  with  good  gun-powder  on  the 
bottom,  it  will  burn  down  and  inflame  the  powder, 

Alcohol  has  such  a  strong  affinity  for  water., 
that  on  mixing  them  they  unite  so  closely  as  to  di- 
minish their  measure,  or  volume. 


228        VEGETABLE  SUBSTANCES. 

Illustration.  Fill  the  bulb  of  a  bolt-head,  or 
long- necked  matrass,  with  water.  Incline  it  a 
little,  and  pour  in  alcohol  to  fill  the  neck  almost 
full.  Let  it  glide  down  slowly  along  the  inside 
of  the  neck,  so  that  it  may  chiefly  float  on  the  sur- 
face of  the  water.  Having  previously  tied  a  piece 
of  a  thread  around  the  neck,  slide  it  to  the  precise 
level  of  the  surface  of  the  alcohol.  Now  put  the 
thumb  over  the  mouth  of  the  bolt- head,  and  shake 
it  so  as  to  mix  the  two  liquids.  It  will  now  be 
seen  that  the  surface  of  the  combined  liquids  is 
considerably  lower  than  the  thread. 

Application.  This  diminution  of  the  measure 
of  the  liquids  encreases  their  specific  gravity. 
Consequently  the  reduction  of  alcohol  by  water  is 
indicated  directly,  by  the  increase  of  the  specific 
gravity.  When  perfectly  pure  the  specific  gravity 
of  alcohol  is  0.79,  but  it  can  hardly  be  obtained 
below  0.82.  Pure  alcohol  consists  of  34.32 
oxygen,  13.10  hydrogen,  and  51.98  earbon. 

Alcohol,  boiled  with  sulphuric  acid,  produces  a 
light  volatile  compound,  called  ether. 

Illustration.  Having  fitted  the  beak  of  a  retort 
to  a  tubulated  receiver,  as  directed  in  obtaining 
alcohol,  immerce  the  receiver  in  cold  water,  or 
surround  it  with  ice.  Raise  the  heat  in  the  lead 
pot  considerably  ;  but  do  not  put  in  the  retort  yet. 
Put  some  alcohol  into  a  tumbler,  and  add  the  same 
weight  (or  a  little  more  than  half  the  bulk)  of  sul- 
phuric acid.  The  acid  must  be  poured  in  gradu- 
ally, and  well  stirred,  as  it  drops  in,  with  a  glass 
rod.  If  it  is  poured  in  fast  it  will  become  too  hot ; 
but  it  must  not  be  so  hot  that  the  heat  of  the  tumb- 
ler cannot  be  borne  by  the  hand.  As  soon  as  it  is 
mixed,  set  the  retort  into  the  lead  pot,  and  immc 


VEGETABLE    SUBSTANCES.  229 

diately  pour  into  it  the  mixed  liquids  through  the 
tubulature,  and  put  in  the  stopper.  Raise  the 
heat  to  a  little  below  the  boiling  point  of  water 
immediately,  and  keep  it  at  that  temperature. — 
This  may  be  determined  by  frequently  dipping  a 
small  stick  into  hot  water,  and  touching  it  to  the 
hottest  part  of  the  retort.  It  must  not  be  quite 
hissing  hot.  If  the  stick  is  dipped  into  cold  wa- 
ter it  may  break  the  retort. 

Continue  the  process  until  the  whole  liquid  in 
the  retort  begins  to  rise  up.  Then  either  stop  the 
process,  or  pour  in  half  as  much  alcohol  as  at  first, 
and  more  may  be  brought  over.  If  the  vapour 
presses  too  hard  during  the  process,  open  the  tu- 
bulature of  the  receiver  an  instant,  occasionally. 

Application.     By  adopting  this  method  of  pre- 
paring ether,  with  large  retorts  and  receivers,  phy- 
sicians and  artists  may  prepare  the  best  of  sul 
phuric  ether,  and  thereby  avoid  both  expense  and 
imposition. 

Ether  is  extremely  volatile  ;  so  that  if  a  part  of 
the  atmospheric  pressure  is  taken  off,  it  will  boil 
with  the  warmth  of  the  hand. 

Illustration.  Put  a  little  ether  into  a  long-neck- 
ed vial  (a  cologne  vial  is  best.)  Heat  the  vial  so 
that  it  can  hardly  be  borne  by  the  hand,  while  its 
mouth  is  open.  Then  put  in  the  cork  perfectly 
tight.  Now  if  a  warm  hand  be  clasped  around 
the  neck  of  the  vial,  and  it  be  held  with  the  bot 
torn  up,  the  ether  will  boil. 

Application.  This  experiment  is  an  additional 
confirmation  of  the  principle  given  under  Caloric, 
p.  30.  It  exhibits  the  volatile  nature  of  ether  also; 
upon  which  much  of  its  usefulness  depends. 

20 


230        VEGETABLE  SUBSTANCES. 

Fermented  liquids  which  produce  alcohol  will 
undergo  a  second  fermentation,  if  exposed  to  warm 
atmospheric  air  ;  in  which  state  the  alcohol  will  be 
destroyed  and  vinegar  will  be  produced. 

Illustration.  Expose  a  little  cider,  strong  beer, 
or  wine,  to  a  summer's  sun,  or  to  the  air  of  a  warm 
room  in  an  open  bowl  or  an  earthen  plate,  and  in 
a  few  days,  or  sometimes  in  a  few  hours,  it  will 
become  acetous,  and  lose  all  its  alcoholic  princi- 
ple. 

Application.  Upon  this  principle  common  vin- 
egar is  made.  Oxygen  is  absorbed  from  the  at- 
mosphere, which  is  supposed  to  unite  with  and 
carry  off  another  proportion  of  carbon  in  the  state 
of  carbonic  acid  gas.  Pure  acetic  acid  consists  of 
46.82  oxygen,  6.35  hydrogen,  48.83  carbon. 

If  good  sound  wood  be  heated  in  a  confined  sit- 
uation, as  in  a  gun-barrel,  &c.  the  pyroligneous 
acid  comes  over,  which  makes  good  vinegar  when 
separated  from  several  impurities  which  come  over 
with  it.  Vast  quantities  of  this  acid  are  produced 
in  the  manufacture  of  charcoal  for  making  gun- 
powder. 

Acetic  acid,  the  pure  basis  of  vinegar,  is  best 
obtained  by  combining  common  vinegar  with  the 
oxid  of  a  metal,  forming  a  salt,  as  acetate  of  cop- 
per (verdegris)  acetate  of  lead,  (sugar  of  lead)  and 
then  distilling  it  over  by  heating  the  salt  to  redness. 

When  wine  becomes  partly  acetous,  called 
pricked  wine,  the  disagreeable  taste  is  often  cor- 
rected by  sugar  of  lead.  It  is  then  poisonous,  and 
the  fraud  ought  to  be  detected.  This  may  be  done 
by  dropping  it  into  a  little  water,  charged  with 
sulphuretted  hydrogen  gas.  It  will  immediately 
become  dark  brown. 


231 

•v 

ANIMAL  SUBSTANCES. 

ULTIMATE  ELEMENTS. 

The  essential  ultimate  elements  of  animal  sub- 
stances are,  carbon,  oxygen,  hydrogen  and  nitro 
gen.  Generally  sulphur  and  phosphorus  are 
found  in  animal  matter. 

The  addition  of  nitrogen  causes  the  most  im- 
portant distinctions  between  animal  and  vegetable 
substances.  It  being  one  of  the  constituents  of  am- 
monia, it  gives  rise  to  that  gas,  during  the  decom- 
position of  animals,  by  the  process  called  putre- 
faction. Several  other  substances  are  frequently 
found  in  animal  matter  ;  as,  oxid  of  iron,  lime, 
soda,  potash,  &c. 

PROXIMATE  ELEMENTS. 

The  most  important  proximate  elements  of  ani- 
mal substances  are,  gelatine,  albumen,  fibrin  and 
oil. 

Gelatine.  This  substance  is  commonly  seen  in 
the  form  of  glue  and  isinglass.  Gelatine  consti- 
tutes a  large  proportion  of  the  skins  of  animals, 
&c.  It  has  a  strong  affinity  for  tannin.  This  will 
appear  by  dropping  an  infusion  of  tannin  (from 
common  nut  galls  will  do)  into  a  solution  of  isin- 
glass. A  pretty  solid  precipitate  will  be  formed 
of  the  union  of  tannin  and  gelatine.  On  this  prin- 
ciple leather  is  formed  ;  the  gelatine  of  skins  com- 
bining with  the  infusion  of  tannin  obtained  by 
soaking  bark  in  water.  It  is  not  coagulated  by 
sulphuric  acid  diluted. 

Mbumen.  This  substance  is  the  most  distinct- 
ly exhibited  in  the  white  of  eggs.  It  always  con- 


232  ANIMAL    SUBSTANCES. 

fains  so  much  soda  as  to  give  the  alkaline  test  with 
red  cabbage.  This  may  be  shown  by  dissolving 
it  in  pure  water,  and  dropping  in  the  infusion  of 
red  cabbage?  which  will  give  the  green  test  of  al- 
kalies. It  is  immediately  coagulated,  and  at 
length  charred  by  sulphuric  acid. 

fibrin.  The  constituent  of  the  fibrous  part  of 
muscles,  &c.  Fibrin  and  albumen  are  the  princi- 
ple constituents  of  blood.  If  a  stream  of  blood 
from  a  vein  runs  through  a  fine  camel-hair  brush, 
iine  fibres  may  be  seen  attached  to  the  hairs,  after 
the  red  globules  have,  been  carefully  soaked  off. 

Oil.  This  appears  in  the  form  of  lard,  tallow, 
spermaceti,  &c.  It  is  divided  into  the  stearine 
and  elawe  parts  like  fixed  vegetable  oil.  Oil  and 
albumen  are  the  principal  constituents  of  milk.  It 
is  slowly  soluble  in  alcohol  and  not  precipitated 
by  water. 

Remark.      Several  more  proximate  elements 
are  described  by  chemists,  but  they  are  of  little 
importance  to  those  for  whom  this  work  is  intend 
ed. 

BONES  AND  SHELLS. 

Internal  bones  of  animals  consist  mostly  of  phos- 
phate of  lime.  They  contain  a  little  carbonate  of 
lime  and  some  animal  matter. 

External  shells  of  animals  are  chiefly  carbonate 
of  lime.  They  generally  contain  a  little  phos- 
phate of  lime,  and  some  animal  matter.  Those 
animals  which  are  covered  with  an  external  crust, 
as  the  lobster,  &c.  have  their  covering  chiefly 
made  up  of  nearly  equal  proportions  of  carbonate 
of  lime  and  phosphate  of  lime,  which  contains  % 
larger  proportion  of  animal  matter. 


ANIMAL  SUBSTANCES.  233 

RESPIRATION. 

Oxygen  changes  the  dark  colour  of  blood  of  the 
veins,  to  the  scarlet  colour  of  arterial  blood, 

Illustration.  Drop  a  small  mass  of  dark  clot- 
ted blood  into  a  vial  of  carbonic  acid  gas,  and 
another  mass  into  a  vial  of  oxygen.  Place  the 
fingers  over  the  mouth  of  each,  and  shake  them 
pretty  hard.  The  blood  in  the  oxygen  will  be- 
come scarlet  coloured,  while  that  in  the  carbonic 
acid  will  remain  dark  coloured.  If  atmospheric 
air  is  now  substituted  for  oxygen,  and  another 
portion  put  in,  it  will  become  scarlet  coloured,  but 
not  so  bright. 

Application.  It  appears  from  this  experiment, 
that  oxygen  may  affect  the  blood  in  respiration,  so 
as  to  produce  the  necessary  change  required  (at 
least  in  the  colour)  for  rendering  it  a  fit  material 
for  supplying  the  waste  of  the  system, 

Atmospheric  air  suffers  a  diminution  of  bulk  by 
respiration  •;  an&  the  oxygen  is  consumed,  or  di- 
minished in  quantity* 

Illustration.  Put  a  mouse  into  a  glass  cylinder) 
and  invert  it  over  mercury,  pressing  it  down  into 
the  mercury  for  a  few  minutes  at  first,  so  that  the 
pressure  of  the  mercury  may  prevent  the  escape  of 
air  by  the  warmth  of  the  mouse.  Let  tiie  mouse 
remain  until  it  expires  ;  whicli  will  be  in  about 
lialf  an  hour  in  a  half  pint  cylinder.  The  mercury 
will  now  be  found  to  have  ascended  a  little  in  the 
cylinder.  If  great  exactness  is  required,  let  the 
temperature  be  regulated  by  the  thermometer  ;  so 
that  the  operator  may  be  certain,  that  the  air  is 
not  more  expanded  when  the  mouse  is  put  in  than 
afterwards. 

20* 


234  ANIMAL   SUBSTANCES. 

Now  take  out  the  mouse  through  the  mercury, 
fill  a  slender  tube  or  test  glass  with  mercury  and 
pour  up  the  contents  of  the  cylinder  into  it.  Turn 
the  open  end  upwards  and  hold  the  finger  on  it 
two  or  three  minutes.  The  gases  within  it  will 
separate.  Carbonic  acid  will  settle  at  the  bottom, 
and  nitrogen  will  rise  towards  the  top.  This  may 
be  proved  by  immersing  in  the  -top  only,  a  small 
burning  taper.  It  will  be  extinguished  two  or 
three  times,  and  afterwards  will  continue  to  burn 
near  the  top.  Let  it  now  stand  open  several  min- 
utes, and  then  immerse  the  taper  to  the  bottom  and 
it  will  be  extinguished.  The  nitrogen  being  light- 
er than  atmospheric  air  ascends,  and  atmospheric 
air  takes  its  place  ;  but  carbonic  acid  being  heavi- 
er remains  at  the  bottom. 

Application.     Several  important  principles  are 
illustrated  by  this  experiment.     A  crowded  as 
sembly  in  a  close  room  consume  the  oxygen  and 
give  off  carbonic  acid  gas.     The  excess  of  nitro 
gen  ascends  to  the  upper  ceiling,  while  the  carbon- 
ic acid  settles  down  near  the  floor.     Consequently 
the  purest  air,  or  that  which  contains  most  oxy 
gen,  is  between  the  two. 

The  diminution  of  the  bulk  of  air  in  the  cylin 
der  is  a  strong  argument  against  a  late  theory  of 
Allen  and  Pepys  respecting  respiration.  The  old 
theory,  which  this  experiment  seems  to  support  iu 
some  measure,  supposes  the  change  produced  in 
the  blood  to  be  caused  by  an  additional  portion  of 
oxygen,  which  is  received  from  the  inhaled  air, 
through  the  thin  membranes  of  the  lungs.  The 
theory  of  Allen  and  Pepys  supposes  the  blood  to 
be  decarbonated,  by  the  union  of  a  portion  of  car- 
bon given  off  in  the  lungs  with  oxygen  of  the  in- 


ANIMAL    SUBSTANCES*  285 

lialetl  air.  But  this  theory  requires  that  the  bulk 
of  the  air  in  the  glass  cylinder  should  neither  be 
increased  nor  diminished.  For  the  addition  of 
carbon,  in  forming  carbonic  acid,  although  it  in- 
creases the  specific  gravity,  does  not  increase  nor 
diminish  the  bulk  of  the  gas.  See  illustration  at 
pages  107  and  108. 

Animal  effluvia,  arising  from  the  beds  of  the  siclc 
or  from  other  sources,  may  be  neutralized  by  the 
strong  acids  in  the  state  of  gas. 

Illustration.  It  seems  to  be  proved  by  observa 
tion  that  such  effluvia  are  combined  with  aqueous 
vapour.  The.  ready  union  of  aqueous  vapour  and 
the  strong  acids  in  the  state  of  gas  will  appear  by 
first  pouring  a  tea-spoon  of  muriatic  acid  upon 
a  red  hot  iron  shovel,  and  then  pouring  a  wine- 
glass of  water  upon  it.  The  acid  will  rise  up  in 
the  state  of  a  suffocating  gas,  and  the  water  will 
follow  it  in  the  state  of  vapour  and  absorb  it  almost 
instantaneously,  so  that  the  suffocating  gas  will 
wholly  disappear. 

Application.  Contagious  vapour  arising  from 
the  beds  of  the  sick,  the  marsh  miasmata  (carbu- 
retted  hydrogen  combined  with  aqueous  vapour) 
and  other  pestilential  effluvia,  may  be  neutralized 
as  follows :  Remove  the  sick  and  other  persons 
from  the  room.  Set  a  tea-cup  or  gallipot  on  the 
floor,  half  filled  with  table  salt.  Pour  into  it 
strong  sulphuric  acid,  and  the  room  will  be  filled 
•with  muriatic  acid  gas.  After  a  few  minutes  open 
the  windows,  and  the  air  of  the  room  will  be  pu- 
rified. 

ACIDS. 

Animal  matter  highly  heated  in  contact  with  pot* 
-ash  will  yield  the  prussic  acid,  (the  most  active  of 


236  ANIMAL    SUBSTANCES. 

all  known  poisons )  and  the prnssiate  of  potash  will 
be  formed. 

Illustration.  Put  some  shavings  of  hides,  which 
raay  be  procured  &i  the  tanners,  into  a  crucible, 
and  invert  another  crucible  over  it,  as  directed  at 
page  102.  Heat  it  until  it  becomes  considerably 
charred  ;  then  take  it  out  and  reduce  it  to  a  coarse 
powder.  Boil  some  potash  in  a  ladle  and  con- 
tinue the  heat  until  the  potash  is  reduced  to  a  dry 
granulated  mass.  Mix  the  two  substances  in 
about  equal  parts,  and  heat  the  mixture  in  a  ladle 
pretty  closely  covered  with  a  sheet  of  iron.  liaise 
the  heat  until  the  blaze  which  leaks  out  under  the 
cover  becomes  whitish  or  nearly  colourless.  Now 
pour  this  mass  into  boiling  water,  and  continue  the 
heat  some  time.  Skim  oil'  all  carbonaceous  and 
other  substances  which  rise  to  the  surface.  When 
no  more  rises,  stop  the  heat.  This  is  the  liquid 
prussiate  of  potash.  It  may  be  evaporated  and 
form  imperfect  crystals. 

Application.  This  is  the  most  delicate  test  for 
detecting  the  presence  of  iron.  But  the  experi- 
ment is  difficult  to  be  performed  before  a  class* 
and  hardly  to  be  recommended.  Prussiate  of  pot- 
ash may  be  purchased  of  the  druggists. 

A  solution  of  the  prussiate  of  potash  will  form 
the  prussiate  of  iron  (prussian  blue)  by  double  de- 
composition with  a  solution  of  sulphate  of  iron. 

Illustration.  Dissolve  some  copperas  in  a  wine- 
glass, and  an  extremely  small  piece  of  prussiate  of 
potash  in  another.  Put  a  drop  of  the  solution  of 
prussiate  of  potash  into  the  copperas,  and  a  prus- 
sian blue  precipitate  will  be  formed. 

Application.     On  the  principle  of  the  two  last 


ANIMAL   SUBSTANCES.  23r 

experiments,  the  prussian  blue  is  manufactured  in 
the  large  way. 

Prussiate  of  potash  may  be  decomposed  andprus- 
state  of  mercury  formed,  by  boiling  it  with  nitric 
oxid  of  mercury,  (red  precipitate.) 

Illustration.  Pulverize  some  common  prussian 
blue  and  put  it  into  a  floreuce  flask.  Put  in  about 
half  and  one  eighth  as  much  red  precipitate.  Then 
pour  in  about  three  times  as  much  pure  water 
(calling  a  pint  a  pound)  as  of  the  prussian  blue: 
and  boil  the  mixture  until  the  red  precipitate  en- 
tirely disappears.  This  will  produce  the  prus- 
siate  of  mercury  in  the  liquid  state.  It  may  be 
strained  through  paper,  and  about  one  fourth  as 
much  boiling  water  as  was  put  in  at  first  may  be 
added. 

Application.  This  salt  is  not  much  used,  ex- 
cepting for  the  purpose  of  procuring  pure  prussic 
acid.  For  this  use  it  is  best  to  keep  it  in  the  liquid 
slate,  as  above  directed  to  be  made,  closely  corked 
up  in  vials. 

Prussic  acid  may  be  obtained  from  theprussiate 
of  mercury  by  heat. 

Illustration.  Fit  a  long-necked  tubulated  retort 
to  a  tubulated  receiver.  Surround  the  receiver 
with  snow  or  ice,  and  set  the  retort  into  the  lead 
pot  in  which  the  coals  are  but  very  little  heated, 
Pour  into  the  retort  some  of  the  liquid  prussiate  of 
mercury  prepared  as  above,  through  the  tubula- 
ture.  Pour  about  one  eighth  part  as  much  pure 
water  through  the  tubulature  into  the  receiver ; 
and  fit  a  waste  pipe  into  the  tubulature  which  may 
conduct  off,  into  water  or  elsewhere  out  of  the 
way,  hydrogen  and  any  other  offensive  gas  which 
in  ay  arise. 


ANIMAL   SUBSTANCES. 

In  order  duly  to  regulate  the  heat,  &c.  now  put 
into  the  retort  through  the  tubulature  about  half  as 
much  by  weight  of  pure  fine  iron  filings,  as  was 
used  of  the  prussian  blue.  All  being  ready,  now 
pour  in  as  much  strong  sulphuric  acid  by  weight 
as  of  the  iron  filings,  and  instantly  \vring  in  the 
glass  stopper  very  tight.  Blow  very  lightly  into 
the  air  hole  of  the  lead  pot  with  the  hand  bellows, 
so  as  to  raise  the  heat  a  little ;  but  not  so  as  to  boil 
nor  even  to  simmer  the  liquid.  Hydrogen  gas  will 
pass  into  the  receiver  and  out  at  the  waste  pipe. 
The  prussic  acid  will  come  over  in  a  state  of  va- 
pour, and  being  condensed  by  the  cold  of  the  ice, 
£c.  will  run  down  and  unite  with  the  water  in  the 
receiver.  After  it  appears  that  about  two  thirds 
as  much  liquid  is  in  the  receiver  as  would  equal 
the  weight  of  the  prussian  blue  (calling  a  pint  of 
the  liquid  a  pound)  stop  the  process,  cork  up  the 
prussic  acid  in  vials  and  put  it  into  a  dark  cellar, 
which  is  cool  in  summer  and  warm  in  winter. 

Application.  This  substance  is  lately  used  in 
consumptive  cases.  Two  or  three  drops  are  dilut- 
ed in  a  large  quantity  of  water.  It  is  the  mostac 
tive  narcotic  known.  Two  or  three  drops  on  a 
large  dog's  tongue  or  in  the  corner  of  its  eye,  will 
kill  it  in  one  or  two  seconds.  It  is  too  dangerous 
an  article  to  make  or  to  use  before  a  class.  Let  it 
be  described  to  the  class  ;  but  it  should  be  made 
in  the  private  office  only.  A  small  quantity  is 
found  in  the  meats  of  almonds,  peach  stones,  cher- 
ry bark,  the  laurus  cerasus,  &c.  And  the  scent 
of  the  prussic  acid  considerably  resembles  the 
odour  of  these  vegetables. 

Some  chemists  place  this  substance  among  the 
vegetable  acids,  because  it  is  found  in  vegetables 


ANIMAL    SUBSTANCES,  23$ 

and  not  in  animals.  Since  it  is  produced  from 
animal  substance  I  have  placed  it  here  ;  though  I 
do  not  contend  for  the  propriety  of  this  location. 

The  basis  of  this  acid  is  found  by  Gay  Lussac 
to  consist  of  carbon  and  nitrogen.  It  is  the  car- 
buret of  nitrogen,  by  some  called  cyanogen. 

Remark.  The  remaining  animal  acids,  enu- 
merated by  authors,  are  of  little  use ;  and  many  of 
them  are  not  well  defined.  That  which  is  most 
worthy  of  the  particular  attention  of  the  house- 
keeper is  the 

Sebacic  acid.  It  is  this  acid  which  is  so  readi- 
ly produced  by  butter  or  fat,  giving  it  a  disagree- 
able  rancid  flavour.  Butter  with  this  flavour  is 
called  frowy  butter  in  New-England.  This  acid 
may  be  neutralized  by  any  of  the  alkalies.  Pearl- 
ash  or  carbonate  of  soda  will  do  it  effectually.  If 
a  little  pearlash  be  dissolved  in  water,  and  the  but- 
ter be  worked  over  with  this  water,  all  the  sebacic 
acid  will  combine  with  the  potash  and  form  a  so- 
luble salt.  If  the  butter  is  then  worked  over  two 
or  three  times  with  pure  water,  the  sebaceate  of 
potash  as  well  as  the  pearlash  will  be  worked  out; 
leaving  the  butter  pure. 

If  cakes,  &c.  be  shortened,  in  the  language  of 
cooks,  with  frowy  butter,  and  pearlash  be  added, 
the  sebacic  acid  will  decompose  some  of  the  pearl- 
ash, and  thereby  furnish  carbonic  acid  to  assist  in 
raising  the  dough.  This  is  the  best  method  of 
using  rancid  butter  or  fat.  Because  the  alkali 
may  sometimes  be  tasted  after  it  has  been  applied 
for  cleansing  as  before  described  5  but  when  used 
for  shortening,  it  cannot. 

DYING. 

Dying  materials  are  either  substantive  or  adjec- 
tive. 


240  ANIMAL    SUBSTANCES. 

Substantive  colouring  matters  are  those  which 
may  be  made  permanent  upon  stuffs  without  a 
mordant ;  as  indigo. 

•Adjective  colouring  matters  are  those  which  can- 
not be  made  permanent  without  the  aid  of  a  mor-, 
dant ;  as  butternut  bark,  logwood,  &c. 

•Mordants  are  the  mediating  substances,  which 
are  used  for  fixing  adjective  colours  ;  as  copperas, 
alum,  muriate  of  tin,  &c. 

Some  colouring  matters  produce  different  co- 
lours when  a  mordant  is  used  ;  others  are  merely 
fixed  by  a  mordant  without  any  change  in  colour. 

Dying  is  too  extensive  a  subject  to  be  presented 
in  detail,  in  this  Instructor.  A  few  principles 
may  be  explained  which  will  prepare  the  student 
for  pursuing  the  subject  under  the  head, 

CALICO  PRINTING. 

Remarks;  In  the  most  simple  operations,  co- 
louring matters  and  mordants  are  applied  several 
times  in  succession,  giving  a  different  colour  at 
every  application.  These  applications  are  made 
with  carved  blocks,  (mostly  cylindrical)  or  by  the 
aid  of  a  defensive  coat  of  wax,  or  of  some  other 
material. 

Illustration.  Prepare  madder  dye  in  the  com- 
mon way — also  a  dye  of  walnut  bark — also  a  dye 
of  indigo.  Cover  parts  of  a  piece  of  white  cotton 
with  melted  white  wax,  and  dip  it  into  acetate  of 
alumine.  Then  melt  off  the  wax  in  hot  water, 
!Now  dip  it  into  the  madder  dye.  Then  wash  and 
bleach  it.  The  dye  will  not  take  where  the  mor- 
dant was  kept  off  by  the  wax. 

Similar  experiments  may  be  performed  with  all 
other  colouring  matters,  using  acetate  of  alumine, 
sulphate  of  iron,  acetate  of  iron,  &c.  Spots  may 


ANALYSIS.  241 

be  made  of  different  colours  by  applying  a  mor- 
dant, mixed  with  paste,  by  means  of  carving  upon 
a  block. 

N.  B.  The  teacher  should  put  large  treatises 
Into  the  hands  of  students,  if  time  will  allow  a  full 
course  ;  as  Bancroft,  Cooper,  &c.  For  very  mi- 
iwte  descriptions  of  particular  manipulations  being 
necessary,  large  systems  must  be  consulted. 

ANALYSIS^ 

_ 

OF  MINERAL  WATERS,  SOILS,  AND  MINERALS, 

Remarks.  To  analize  expertly  and  accurately 
requires  the  practice  of  several  years,  and  an  ex- 
tensive collection  of  the  most  perfect  tests. — The 
presence  of  common  metals  may  be  detected,  with- 
out much  difficulty.  The  substances  which  are 
usually  held  in  solution  in  the  mineral  waters  of 
our  country,  may  be  ascertained  without  a  laborious 
process.  But  to  determine  the  proportions  of  the 
parts  of  a  compound  mineral,  or  the  quantity  of 
any  substance  contained  in  mineral  waters,  re- 
quires in  some  cases,  more  practical  instruction 
than  can  be  communicated  in  the  course  here  pro- 
posed. 

The  directions,  which  are  given  under  this  head, 
are  sufficient  for  ordinary  cases  in  the  analysis  of 
mineral  waters — they  are  still  more  complete  for 
the  analysis  of  soils — but  the  analysis  of  the  sub- 
stances, which  belong  to  the  classes  Metalloids 
and  Metals,  requires  an  extensive  treatise.  A 
mere  outline  is  given  here. 

GENERAL  TESTS  FOR  MINERAL  WATERS,  SOILS 
AND  MINERALS. 

Ms  the  hydro-sulphuret  of  ammonia  will  precipi- 
21 


242  ANALYSIS. 

tate  the  oxids  of  all  metals,  which  form  the  basis 
of  salts,  the  colours  of  the  precipitates  may  assist 
in  detecting  metals. 

Illustration.  Put  very  dilute  solutions  of  sev- 
eral metallic  salts  (as  copperas,  blue  vitriol,  white 
vitriol,  sugar  of  lead,  lunar  caustic,  &c.)  into  sepa- 
rate wine-glasses,  and  pour  in  an  extremely  small 
quantity  of  hydro-sulphuret  of  ammonia  into  each, 
and  observe  the  different  coloured  precipitates. 

Application.  Dissolve  a  supposed  metal  in  an 
acid — as  sulphuric,  muriatic,  nitric  or  nitro-mu- 
riatic.  Prepare  a  solution  of  a  known  metallic 
salt,  as  before  directed,  having  a  base  of  that  met- 
al which  is  suspected  to  be  under  examination. 
Pour  some  hydro-sulphuret  of  ammonia  into  both, 
and  compare  the  colours,  densities  and  other  char- 
acters of  the  precipitate.  Although  this  will  not 
always  afford  conclusive  evidence,  it  will  assist 
in  directing  the  judgment. 

•toi  infusion  of  galls  will  precipitate  the  oxids  of 
many  of  the  metals ,  which  form  the  bases  of  salts  ; 
and  the  colours  of  the  precipitates  may  assist  in  de- 
tecting such  metals. 

Illustration.  Rasp  off  a  quantity  of  nut-gall 
and  soak  it  an  hour  or  two  in  pure  water.  Strain 
off  the  liquid  and  put  it  into  a  phial  for  use.  Dis- 
solve several  metallic  salts  as  directed  in  the  last 
experiment,  and  precipitate  the  oxids  of  the  met- 
als from  their  acids  with  the  infusion  of  the  nut- 
galls,  and  observe  the  colours  of  the  precipitates. 

Application.  Metals  may  be  tested  by  being 
reduced  to  salts  and  by  collateral  er  comparison 
experiments  as  directed  when  using  the  hydro-sul- 
phuret of  ammonia.  It  must  be  understood,  that 
the  same  metal  sometimes  gives  different  coloured 


ANALYSIS.  243 

precipitates,  when  in  different  degrees  of  oxida- 
tion. The  following  are  some  of  the  colours  as 
taken  from  Brande.  With  the  proto-muriate  of 
manganese,  dirty  yellow — proto-sulphate  of  iron, 
purple — permuriateof  iron,  black — muriate  of  tin, 
dirty  yellow — proto-muriate  of  tin,  (acid)  straw 
colour — per-muriate  of  tin,  (acid)  fawn  colour — 
proto-muriate  of  copper,  yellow  brown — per-ni- 
trate  of  copper,  grass  green — nitrate  of  lead,  dingy 
yellow — tartrate  of  antimony  and  potash,  straw 
colour — tartrate  of  bismuth  and  potash,  yellow — 
sulphate  of  uranium,  bluish  black — muriate  of 
titanium,  (acid)  brown — sulphate  of  titanium, 

blood    red white    oxid  of    arsenic,    scarcely 

changed — any  salt  of  molybdena,  brown — sulphate 
of  nickel,  green — proto-nitrate  and  per- nitrate  of 
mercury,  (acid)  yellow — nitrate  of  silver,  curdy 
becoming  brown — muriate  of  platina,  brownish 
green — muriate  of  gold,  wine  colour. 

Though  the  alkalies  will  take  the  acids  from  me- 
tallic oxids  generally  ;  yet  the  metallic  oxid  will 
take  metallic  acids  from  the  alkalies. 

Illustration.  Pour  a  solution  of  chromate  of 
potash  into  solutions  of  several  metallic  salts,  and 
chromates  of  the  metallic  oxids  of  the  salts  will  be 
produced. 

Application.  Proceed  as  directed  under  hydro- 
sulphuret  of  ammonia,  and  much  may  be  learned 
respecting  the  presence  of  metals.  No  precipi- 
tates of  different  metals  will  be  of  a  similar  colour. 
That  of  mercury  will  be  cinnabar  ;  of  silver,  car- 
mine red  ;  of  lead,  orange  yellow,  &c. 

Several  acids,  alkalies,  and  salts,  give  evidence 
of  the  presence  of  mineral  substances  ;  and  there- 
l)y  direct  the  student  in  the  analysis. 


244  ANALYSIS. 

Prussiate  of  potash  gives  the  prussian  blue  pre 
cipitate  with  iron. 

Muriatic  add  gives  the  grey  precipitate  with 
silver. 

Cochineal  in  solution  gives  a  scarlet  colour  to 
muriate  of  tin. 

Sulphuric  acid  will  cause  an  escape  of  bubble? 
of  carbonic  acid  gas,  if  poured  into  carbonated  wa- 
ter. It  takes  barytes  from  any  other  acid,  by 
forming  with  it  a  dense  grey  precipitate. 

Brazil  wood  becomes  yellow  with  acids,  and  its 
original  colour  is  restored  by  an  alkali. 

Nitrate  of  silver  gives  a  dense  grey  cloud  in 
any  solution  containing  muriatic  acid,    whether 
free,  or  combined  with  a  salifiable  base.     On  ex- 
posure to  the  sun?s  rays,  this  grey  cloud  (preci 
pitate)  becomes  blackened. 

Infusion  or  tincture  of  red  cabbage  gives  a  red  co- 
lour when  an  acid  is  free,  or  in  excess,  and  a  green 
colour  when  an  alkali  is  free  or  in  excess.  The 
liuman  breath,  if  introduced  into  the  red  cabbage 
infusions,  gives  a  light  red  colour,  on  account  of 
the  carbonic  acid  manufactured  in  the  lungs. 

Red  cabbage  infusion  gives  a  red  colour  to  wa- 
ter charged  with  sulphuretted  hydrogen  gas.  It 
will  give  the  same  colour  to  cider,  wine,  ale,  &c. 
because  they  contain  a  free  vegetable  acid. 

^i.B.  Red  cabbage  becomes  blue  tyy  standing 
a  few  hours,  if  the  water  in  which  it  is  mashed  is 
pure.  Paper  in  half  incli  slips  dipped  in  a  strong 
infusion  of  red  cabbage,  is  better  adapted  to  such 
xperiments  than  the  liquid  infusion.  On  dipping 
euch  slips  of  paper  into  the  liquid  to  be  tested,  its 
acid  or  alkaline  character  is  shewn  by  the  colour 
of  the  slip  of  paper. 


ANALYSIS.  245 

Turmeric  infusion  is  changed  from  yellow  to 
brick-red  or  orange,  by  alkalies,  whether  free  or 
combined  with  an  acid  ;  but  it  is  not  affected  by 
carbonates  of  the  alkaline,  or  other,  earths. 

JVitric  acid  will  convert  gum,  sugar,  mucilage, 
or  jelly,  into  oxalic  acid  by  long  digestion  with 
Jieat ;  but  heat  produces  no  change  upou  resin, 

It  detects  the  presence  of  starch  if  the  substan- 
ces be  digested  several  days  $  for  alcohol  will  then 
precipitate  it. 

It  detects  nitrogen  in  meat,  &c.  for  if  poured 
upon  meat  in  a  retort,  the  nitrogen  will  come  over 
in  a  state  of  gas. 

It  is  the  only  heavy  acid  which  dissolves  sil- 
ver alone, 

Muriatic  acid  always  forms  awhile  precipitate 
with  silver  or  lead.  The  silver  precipitate  be- 
comes black  on  exposure  to  air. 

It  produces  chlorine  gas  with  per-oxid  of  man 
ganese,  if  sulphuric  acid  be  added. 

Tartaric  acid  when  combined  with  potash, 
forming  the  tartrate  of  potash,  gives  a  crystalline 
precipitate ;  but  if  the  basis  is. soda  the  liquid  will 
remain  limpid, 

Oxalic  acid  (oxalate  of  ammonia  is  better)  will 
always  produce  a  dense  cloud  with  lime,  whether 
free  or  combined. 

Muriate  of  ammonia  gives  a  bright  yellow  (or  a 
little  orange)  precipitate,  with  muriate  of  platina 

Corrosive  sublimate  gives  a  white  flocculent  pre- 
cipitate with  albumen. 

Phosphate  of  soda  is  a  good  flux  with  the  blow- 
pipe, when  deprived  of  its  water  of  crystalliza- 
tion by  heat. 

Lime  water*  perfectly  limpid,  gives  a  grey  cloud 
<with  carbonic  acid,  in  the  state  of  gas  or  in  waterc 
..31* 


MB  ANALYSIS* 

It  gives  a  brick- dust  like  precipitate  with  corrosive 
sublimate.  It  decomposes  salts  of  magnesia,  with 
a  grey  precipitate. 

Tannin  forms  a  solid  precipitate  with  animal 
gelatin. 

Muriate  of  platina  produces  a  yellow  precipi- 
tate with  all  salts  of  potash  ;  but  not  with  soda. 
But  the  solution  must  be  strong,  and  contain  no 
excess  of  acid. 

Sulphate  of  iron  (when  perfectly  green)  produc- 
es a  brown  precipitate  with  any  salt  of  gold  in  so- 
lution. It  gives  a  dark  purple,  and  at  last  black; 
with  gallic  acid. 

Muriate  of  lime  produces  a  white  precipitate 
with  oxalic,  malic,  and  tartarous  acid. 

Benzoate  of  ammonia  precipitates  iron  of  a  yel 
lowish  colour. 

Tincture,  or  infusion,  of  galls  produces  a  violet, 
nnd  at  last  black,  precipitate,  with  any  solution  ot 
Iron. 

Liquid  ammonia  gives  any  solution  of  copper  a 
blue  colour.  Partially  precipitates  salts  of  mag- 
aesia  ;  but  not  salts  oflime. 

Oxalate  of  ammonia  produces  a  grey  precipitate 
with  any  salt  of  lime. 

Prussiate  of  potash  forms  a  precipitate  with  all 
metals  but  platina  and  it  alloys,  gold,  antimony, 
and  teliurium.  As  no  earthy  salt  is  affected  by  it, 
this  circumstance  makes  it  an  excellent  test  for  dis- 
criminating between  metallic  and  earthy  salts. 

JBarytic  water  is  a  substitute  for  lime  water  in 
detecting  the  presence  of  carbonic  acid.  It  is  bet- 
ter than  lime  water. 

Muriate  of  barytes  forms  a  cloud  with  sulphUf 
lie  acid  in  any  state  of  combination. 


ANALYSIS    OJP   MINERAL   WATERS.  247 

Nitrate  of  barytes,  same  as  muriate  ;  but  is  pre- 
ferable in  a  few  cases,  when  muriatic  acid  would 
embarrass  further  experiments. 

£odine  gives  a  purple  colour  to  starch. 

Jllcoh  ol  dissolves  several  proximate  elements  oi' 
vegetables,  which  water  will  not  dissolve.  See  v> 
getade  matter. 

Metallic  %inc  precipitates  lead,  if  there  is  a  lit- 
tle excess  of  acid  in  the  solution. 

Metallic  iron  precipitates  copper  (as  a  knife 
blade,  &c.)  if  there  is  a  little  excess  of  acid. 

Metallic  copper  precipitates  silver,  if  the  acid 
is  a  little  in  excess. 

Black  flux  and  white  flux  are  useful  with  the 
blow -pipe. 

Asbestos  fibres  are  useful  for  wrapping  around 
minerals  to  be  subjected  to  the  blowpipe,  for  hold- 
ing them  steadily.  Minute  specimens  may  be 
fastened  to  the  fibres  with  plastic  clay. 

Charcoal  for  the  blowpipe  is  very  useful.  A  mi- 
neral put  into  a  hole  made  in  the  coal  will  melt 
sooner,  than  if  exposed  to  the  blowpipe  in  the 
common  way. 

ANALYSIS  OF  MINERAL  WATERS. 

The  following  directions  will  be  sufficient  for 
detecting  those  substances  which  most  commonly 
occur,  and  in  the  largest  proportions,  in  the  United 
States.  Prepare  the  following  waters  artificially, 
and  test  them  before  the  class. 

In  searching  for  any  of  these  substances,  it  will 
be  advisable  to  use  the  test  for  that  first  which  we 
have  the  most  reason  to  expect. 

Mu  in  ATE  OF  LIME.  Nitrate  of  silver  in  solu- 
tion dropped  into  the-water  gives  a  dense  white 


IMS  ANALYSIS   OF   MINERAL   WATERS. 

cloud  if  it  contains  muriatic  acid.  Oxalic  acid 
gives  a  light  white  cloud,  if  it  contains  lime.  Ox- 
alate  of  ammonia  is  better. 

SULPHURETTED  HYDROGEN.  JLcetate  of  lead  in 
solution  is  precipitated  dark  brown. 
-,  CARBONATE  OF  IRON.  Tincture  of  galls  gives 
a  dark  purple,  and  at  length  a  brown  colour,  if  it 
contains  iron.  Boiling  will  drive  off  the  carbonic 
acid,  so  that  after  it  has  stood  awhile  the  iron  will 
be  so  completely  precipitated,  that  the  superna- 
tant liquid  will  not  give  the  test  with  the  tincture 
of  galls. 

SULPHATE  OF  IRON.  Tincture  of  Galls  gives 
the  dark  colour  both  before  and  after  boiling. 

FREE  CARBONIC  ACID.  Lime  water  gives  a 
white  cloud  before  boiling,  but  produces  no  effect 
after  boiling. 

SULPHATE  OF  MAGNESIA.     Muriate  of  barytes 

fives  a  cloud,  if  water  contains  sulphuric  acid, 
f  red  cabbage  does  not  give  the  acid  test,  the  sul- 
phuric acid  is  combined  with  a  base.  If  the  tinc- 
ture of  galls  and  oxalic  acid  give  no  test  of  iron  or 
lime,  we  may  presume  the  base  to  be  magnesia. 
To  be  more  sure,  evaporate  the  water  by  a  very 
gradual  heat,  and  taste  the  dried  residuum.  If  it 
has  a  bitter  taste,  it  will  be  a  confirmation  of  the 
tests. 

MURIATE  OF  SODA.  Test  the  muriatic  acid 
by  nitrate  of  silver.  If  oxalic  acid  does  not  give 
the  test  of  lime,  evaporate  it  slowly  to  dry  ness  and 
taste  it.  No  one  can  mistake  the  taste  of  common 
salt. 

Incompatible  salts  are  often  mentioned  in  books. 
But  these  incompatible  salts  often  exist  together 
while  the  water  is  cold  ;  but  as  soon  as  the  water 
is  heated,  decompositions  take  place. 


ANALYSIS   OF   SOILS.  249 

The  preceding  are  not  given  according  to  the 
nice  directions  of  the  books  ;  but  they  will  serve 
as  a  convenient  guide. 

If  lead  be  suspected  in  water  which  has  passed 
through  leaden  aqueducts,  pass  sulphuretted  hy- 
drogen gas  into  a  portion  of  it,  and  if  it  contains 
lead,  it  will  instantly  exhibit  a  dark  brown  tinge. 

If  copper  is  suspected  in  water,  or  in  any  ar- 
ticle of  diet  which  has  stood  in  a  copper  vessel, 
pour  into  it  liquid  ammonia,  and  it  will  become 
blue. 

N.  B.  Always  institute  collateral  experiments 
upon  known  substances,  which  are  similar  to  those 
for  which  you  are  searching.  In  doing  this,  make 
use  of  very  minute  portions  ;  because  large  quan- 
tities may  alter  the  appearance. 

When  it  is  required  merely  to  know  whether 
the  water  is  of  that  kind  called  hard-water,  with- 
out regard  to  the  kind  of  substances  held  in  solu- 
tion, dissolve  a  small  piece  of  fine  hard  soap  in  al 
cohol,  and  pour  a  few  drops  of  this  solution  into 
the  water.  If  it  is  hard  water  it  will  become 
milky — if  no^  ft  wiu  remain  limpid, 

ANALYSIS  OF  SOILS. 

The  object  in  analysing  soils  is  not  to  ascertain 
the  ultimate  constituents  of  soils.  It  is  to  ascer- 
tain the  constituents  of  soils,  so  far  as  such  con- 
stituents have  any  influence  upon  the  growth  of 
plants.  Such  constituents  may  be, 

i.  Stones  above  the  diameter  of  the  fourth  of  an 
inch.  These  stones  serve  to  prevent  the  soil  from 
becoming  too  compact,  and  to  retain  moisture  on 
their  surfaces  ;  and,  in  some  cases,  to  condense 
floating  vapour  when  at  the  surface  of  the  soiL 


250  ANALYSIS    OF   SOILS. 

2.  Pebbles  below  the  diameter  of  the  fourth  of 
an  inch.  These  serve  for  most  of  the  uses  of  stones: 
and,  being  of  a  more  suitable  size,  are  useful  in 
keeping  the  soil  in  a  kind  of  loose  porous  state, 
adapted  to  the  extension  of  roots  and  transmission 
of  moisture. 

The  constituent  elements  of  stones  or  pebbles 
can  have  no  influence  on  the  productiveness  of 
soils  ;  unless  reference  is  had  to  the  future  chang- 
es to  be  effected  by  their  disintegration.  A 
pebble  of  diamond,  sapphire,  or  quartz,  will  have 
the  same  influence  upon  vegetation  ;  though  on  an 
ultimate  analysis  the  first  would  give  carbon,  the 
second  alumine,  and  the  third  silex. 

8.  Siliceous  soil.  This  has  such  a  feeble  at- 
traction for  water,  that  it  will  remain  but  a  shod 
time  suspended  in  it.  Such  a  soil  scarcely  suffers 
by  a  wet  season,  and  does  not  suffer  severely  by  a 
drought.  It  never  "winterkills"  wheat.  But 
it  is  not  a  rich  soil. 

4.  Alluniinous  soil.    This  is  always  in  the  state 
of  an  impalpable  powder.     It  attracts  water  so 
strongly,  that  it  will  remain  long  suspended  in 
water.     Such  a  soil  is  too  soft  in  a  rainy  season, 
and  bakes  hard  in  a  dry  season.  It  requires  a  due 
mixture  with  silicious  soil. 

5.  Lime  soil.     A  soil  which  abounds  in  car- 
bonate  of  lime.    This  may  be  considered  as  a  per- 
manent manure.     Its  ultimate  disintegration  en- 
riches soils. 

6.  Soluble  salts.     Most  salts  of  this  kind  pro 
mote  the  speedy  growth  of  plants.     These,  togeth- 
er with  some  insoluble  salts,  as  gypsum,  pulver- 
ized marble,  &c.  act  as  stimuli,  and  cause  vege- 
tables to  seize  greedily  upon  any  nutriment  with- 


ANALYSIS   OF   SOILS.  251 

in  their  reach,  as  a  glass  of  brandy  excites  strong 
appetite  in  a  healthy  labourer. 

7.  Animal  and  vegetable  matter.     The  basis  of 
these  substances  is  chiefly  carbon.    But  the  whole, 
not  only  furnishes  nutriment  directly  to  plants, 
but  absorbs  from  the  atmosphere  those  gases  which 
are  highly  nutritive   to   them.      This  has   been 
shewn  in  the  preceding  part  of  this  book. 

8.  Water.     Some  soils  hold  more  water  than, 
others,  between  the  drying  heat  of  the  sun  and  a 
heat  sufficient  to  charr  dry  combustible  vegeta- 
bles.    Such  soils  will  resist  the  ill  effects  of  a 
drought. 

9.  Oxid  of  iron.     This  is  always  found  in  soils  ; 
but  its  effects  on  vegetation  seem  not  to  be  settled. 
It  is  probably  useful. 

10.  Powers  of  retaining  water,  so  as  to  remain 
mechanically  suspended  in  it.     This  seems  not  to 
depend  wholly  on  the  proportion  of  the  alumine. 
And  when  ever  any  soil,  or  any  portion  of  it,  will 
remain  suspended  in  water  over  four  hours,  wheat 
sown  in  it  is  often  "  winter  killed." 

The  following  formula  is  an  improvement,  af- 
ter five  year's  experience,  upon  one  adopted  by 
Dr.  T.  llomeyn  Beck,  and  myself,  in  analyzing 
the  soils  of  Albany  and  Rensselaer  counties, 

1.  Several  pounds  of  soil  are  weighed,  which 
was  taken  from  an  average  of  the  field.  The  stones 
are  picked  out  and  weighed,  which  are  above  the 
fourth  of  an  inch  in  diameter,  and  their  percentage 
estimated. 

2.  Six  hundred  grains  of  this  soil  is  weighed 
out,  after  deducting  the  above  percentage,  and  put 
into  a  pint  of  pure  water,  thoroughly  stirred,  and 
allowed  to  settle  one  minute.    All  above  the  sed- 


352  ANALYSIS   OF  SOILS. 

iment  of  pebbles  is  then  poured  off.  The  pebbles 
are  sun-dried,  weighed,  and  their  percentage  esti- 
mated. What  is  poured  off  is  sun-dried,  and  re- 
duced to  an  impalpable  powder  in  a  clean  Wedge- 
wood  mortar. 

3.  One  third  part  is  put  into  a  crucible  and  heat- 
ed gradually,  constantly  stirring  it  with  a  dry  pine 
stick,  until  the  stick  becomes  a  little  brownish  from 
the  heat,  on  pressing  it  against  the  bottom  of  the 
crucible. 

4.  It  is  then  carefully  poured  into  the  scales  and 
again  weighed.     What  is  deficient  is  set  down  as 
water. 

5.  The  parcel  is  then  returned  into  the  crucible, 
and  heated  to  a  high  red  heat.     It  is  frequently 
stirred  with  a  glass  rod,  and  the  heat  is  continued 
until  the  mass  presents  no  shining  sparks.     After 

'  allowing  it  to  cool  a  little,  it  is  returned  into  the 
scales  again,  and  what  it  wants  of  its  last  weight, 
is  set  down  for  the  animal  and  vegetable  matter. 
Part  of  this  remainder  is  undoubtedly  water,  but 
probably  is  not  more  than  should  always  be  con- 
sidered as  attached  to  this  part.  It  may  here  be 
added,  that  there  will  be  no  blackness  in  the 
appearance  of  the  soil,  if  it  has  been  sufficiently 
heated. 

6.  Let  it  now  be  poured  into  an  assay  glass, 
and  half  a  pint  of  pure  water  added  to  it.  After  re- 
peated stirring  for  ten  minutes,  let  it  stand  about 
three  minutes  to  allow  the  siliceous  matter  to  set- 
tle.  Then  pour  off  all  which  stands  over  the  sili- 
ceous part  into  another  glass.     Dry  this  sediment 
in  a  high  red  heat,  weigh  it  and  set  it  down  for  the 
siliceous  soil. 

1*  Lei  the  part  which  was  transferred  to  another 
glass,  stand  until  it  settles,  leaving  the  liquid  clear. 


ANALYSIS    OF   SOILS.  253 

Pour  off  the  liquid  into  another  glass,  dry  this  se- 
diment with  a  high  red  heat,  weigh  it,  and  set  it 
down  for  the  aluminous  soil. 

8.  The  remaining  liquid  is  then  evaporated  in 
a  glass  evaporating  dish.     The  solid  residuum  is 
scraped  off,  and  weighed  for  soluble  salts. 

9.  Another  third  part  is  put  into  a  florence  flask, 
in  which  half  a  gill  of  equal  portions  of  muriatic 
acid  and  water  Iras  previously  been  poured,  and 
which  has  also  been  balanced  by  weights  in  the 
scales.     After  allowing  it  to  stand  about  three 
hours,  it  is  ascertained  how  much  less  than  its 
former  weight  is  to  be  added  to  the  weight,  in  or- 
der to  balance  the  flask.     It  must  be  remembered 
that  the  carbonic  acid  is  to  be  blowed  out  of  the 
flask  with  a  bellows,  before  it  is  weighed.     This 
is  considered  as  the  weight  of  the  carbonic  acid 
that  1ms  been  expelled.     Then  by  the  table  of 
component  parts,  as  44  is  to  56,  so  is  this  weight 
to  the  weight  of  the  base.     The  carbonate  of  lime 
In  the  soil  is  thus  ascertained.     The  lime,  how- 
ever, must  be  subtracted  from  the  silex,  and  the 
weight  of  the  carbonic  acid  must  be  deducted  from 
the  animal  and  vegetable  matter ;  since  the  heat 
that  burnt  out  the  animal  and  vegetable  matter,  al- 
so expelled  the  carbonic  acid,  and  left  the  lime 
with  the  siliceous  soil. 

We  are  aware  that  part  of  the  quick  lime  may 
remain  with  the  soluble  salts,  and  part  of  the  car- 
bonic acid  may  still  remain  with  its  base  and  the 
sflex.  The  error,  however,  will  be  of  no  conse- 
quence IB  agriculture. 

10.  Boil  the  last  third  in  sulphuric  acid,  and 
thus  obtain  a  sulphate  ef  iron.     Precipitate  the 
iroa  with  prussiate  of  gotash.    Then  pour  off  all 

22 


254  ANALYSIS    OF  MINERALS. 

the  liquid,  dry  and  weigh  the  solid  blue  prussiate 
of  iron.  Then  by  the  per  cent  tables  it  appears 
that  30.80  of  this  salt  is  protoxid  of  iron — peroxitl 
being  34.23. 

Average  specimens  of  soil  from  near  Albany  anil 
Troy,  N.  Y. 

Upland  loam.  Silex  67  per  cent — Alumine  22 
— Carbonate  of  lime  1 — Soluble  salts  1 — Decom- 
posed animal  and  vegetable  matter  5 — Water  4= 
100.  Settled  clear  in  4  hours. 

Best  lowland  loam.  Silex  f>6 — Alumine  25— 
Carbonate  ot  lime  2 — Soluble  salts  1 — Decompos* 
ed  animal  and  vegetable  matter  12 — Water  4= 
100,  Settled  clear  in  3  hours. 

Best  river  alluvion  where  water  stands  three  or 
four  feet  below  the  surface.  Silex  75 — Alumine 
7 — Carbonate  of  lime  3 — Soluble  salts  i — Decom- 
posed animal  and  vegetable  matter  11 — Water  3= 
100.  Settled  clear  in  2  hours. 

Clay  alluvion.  Siliceous  soil  48 — alluminous 
39 — carbonate  of  lime  2 — soluble  salts  2 — animal 
and  vegetable  matter  5 — water  4=100.  Settles 
clear  in  26  hours. 

Stones  and  pebbles  were  included  under  silex. 
or  siliceous  soil,  in  all  these  analyses. 

Note.  If  the  oxid  of  iron  is  sought,  most  soils 
will  yield  from  1  to  3  per  cent. 

ANALYSIS  OF  MINERALS. 
After  the  student  has  prepared  or  procured,  the 
general  tests,  and  applied  them  in  the  analysis  of 
Mineral  waters,  and  familiarized  himself  with 
their  appearances  in  artificial  as  well  as  natural 
liquids,  he  should  proceed  to  the  analysis  of  solid 
minerals. 


ANALYSIS    OF   MINERALS.  255 

Most  solid  minerals  must  be  brought  to  the  li- 
quid state  before  tests  are  applied.  In  many  cases 
a  mere  mechanical  suspension  in  water  will  serve 
the  same  purpose  as  a  chemical  solution. 

Analysis  of  minerals  is  very  properly  divided 
into  the  approximating  process  and  the  propor- 
tioning process. 

APPROXIMATING    PROCESS. 

1.  Determine  the  character  of  the  mineral,  as 
nearly  as  possible,  by  the  external  characters,  ac- 
cording to  the  most  approved  systems  of  Mineral- 
ogy.    Cleaveland  and  Emmons  are  the  best  now 
in  use  in  this  country. 

2.  Pulverize  the  mineral  in  quantities  five  or 
BIX  times  as  great  as  you  intend  to  analyse  ;4gen 
erally  about   500  grains.     Most  minerals,  espe 
cially  those  of  the  silicious  kind,  require  to  be 
heated  to  a  high  red  heat  and  plunged  into  water. 

All  minerals  must  be  pounded  and  rubbed  ve- 
ry fine.  Most  failures  in  analysis  may  be  ascrib- 
ed to  a  want  of  attention  to  this  part  of  the  pro- 
cess. The  mineral  must  be  so  fine  as  to  become 
somewhat  of  a  paste  or  cake,  when  dry. 

3.  Stir  up  a  little  of  the  powder  in  pure  cold 
water — let  it  settle  a  little,  so  as  to  become  partly 
clear.     Put  a  little  of  this  into  several  wine  glass 
es.     Test  it  separately  by  hydro-sulphuret  of  am- 
monia, nut-galls,  prussiate  of  potash,  chromate  of 
potash,  oxalic  acid,  nitrate  of  silver,  muriate  of 
barytes,  acetate  of  lead.     Write  down  the  appear- 
ance produced  by  each  test ;  and   against  each 
write  the  name  of  the  mineral  substance  it  indi 
cates,  according  to  the  rules  set  down  under  gen- 
eral tests. 


256  ANALYSIS    OF   MINERALS. 

4.  Gk>  through  the  same  process,  given  undev 
No.  3,  with  boiling  water,  if  doubts  still  remain. 

5.  Gro  through  with  same  process,  given  under 
No.  3,  with  sulphuric  acid,  muriatic  acid,  nitric 
acid,  and  nitro- muriatic  acid  ;  unless  some,  or  al!5 
the  trials,  have  demonstrated  the  presence  of  all 
the    constituents    whicli  can  be  present  in  the 
mineral,  without  this  step. 

After  this  last  step  has  been  taken,  if  a  consid 
erable  part  of  the  mineral  remains  in  a  solid  state* 
proceed  as  follows  : 

6.  Mix  a  weighed  portion  with  three  times  its 
weight  of  pure  solid  potash,  and  dissolve  it  in  pure 
water,  (or  rather  stir  it  up  so  as  to  bring  it  to  a  kind 
of  mechanical  suspension  in  it.) 

7.  Put  this  mixture  into  a  cast-iron  crucible 
(silver  or  platina  would  be  preferable)  and  apply 
lieat  moderately  and  stir  it  continually.     Raise 
the  heat  a  little  gradually  until  all  the  water  is 
evaporated.     Now  raise  the  heat,  and  keep  the 
mixture  red-hot  half  an  hour  ;  or  until  the  whole, 
or  most  of  it,  becomes  liquid.     The  liquid  part  is 
silex.     But  it  is  difficult  to  separate  it  by  pouring. 
We  can  only  obtain  a  general  knowledge  of  the 
mineral  by  this  step.     Such  as,  that  if  it  is  most 
ly  liquid  and  limpid,  it  is  mostly  silex — if  it  is 
dense,  opaque,  and  paste-like,  it  contains  but  lit- 
tle silex — if  it  is  in  a  pulverized  state,  it  is  chiefly 
alumine. 

Thus  far  we  merely  approach  the  desired  re- 
sult. In  pursuing  the  analysis,  we  depart  from 
the  usual  complicated  method,  which  takes  along 
every  constituent  of  the  specimen  at  the  same 
time.  We  find  it  to  be  much  more  simple  and 
r  convenient  to  seek  the  proportion  of  each  constifa* 


ANALYSIS    OF   MINERALS, 


257 


ent  of  a  compound  separately,  as  though  it  was  the 
only  ohject  of  research.  Then  proceed  with  an- 
other specimen  of  the  same  mineral  upon  the  same 
plan ;  and  so  on,  until  every  substance,  indicated 
by  the  tests,  be  separately  ascertained, 

PROPORTIONING    PROCESS, 

8.  Having  thus,  by  the  aid  of  mineralogy,  and 
general  tests,  either  ascertained  the  true  character 
of  the  mineral,  or  brought  it  within  narrow  limits, 
we  enter  upon  the  necessary  analysis  for  ascertain-* 
ing  the  proportional  constituents,  as  follows  : 

9.  In  our  district  of  country  we  are  to  expect  in 
a  specimen  some  of  the  following  minerals  ;  and 
rarely  any  other : 

6.  CHROME, 

ferriferous, 
oxid  of  chrome, 
chromate  of  iron, 
carbonate  of  chrome 

7.  SILVER, 

sulphuret  with  lead ., 


1.  IRON, 

protoxid, 

hematitic, 

argillaceous, 

(lenticular  &  bog) 
carbonate, 
sulphuret, 
carburet, 
sulphate. 

2.  LEAD, 

galena. 

3.  ZINC, 

blende, 

calarnine, 
1.  COPPER, 

pyrites, 

carbonate. 
5.  MANGANESE, 

peroxid, 

argillaceous-* 


8.  GOLD. 

9.  BISMUTH. 

10.  COBALT, 

arseniate. 

11.  MOLYBDENA. 

sulphuret. 

12.  ANTIMONY. 

13.  TITANIUM, 

red  oxid. 

14.  LIME, 

carbonate,, 

sulphate, 

muriate* 


358  ANALYSIS    OF  MINERALS, 


fluate, 
phosphate. 

15.  BARYTES, 

sulphate. 

16.  STRONTIAN, 

sulphate. 

17.  MAGNESIA, 

sulphate. 


18.  SODA, 

muriateo 

19.  POTASH, 

nitrate. 

20.  ALUMINE, 

sulphatCc 

21.  SILEX. 

22.  COAL. 


23.    BlTUMENo 

When  the  presence  of  any  df  these  minerals  is 
detected  in  a  specimen  under  examination,  by  the 
external  characters  given  in  systems  of  mineralo 
gy  or  by  the  general  test,   a  further  analysis  may 
be  made  as  follows  : 

10.  Iron  ore,  whether  magnetic,  hematitic,  ar- 
gillaceous, or  carbonate,  should  be  dissolved  in 
muriatic  acid,  renewing  the  acid  several  times  and 
pouring  off  the  clear  liquid,  and  precipitated  by 
carbonate  of  soda  from  the  liquid  poured  off.  Dry 
the  precipitate  after  several  washings,  and  the  pro 
toxid  is  obtained.  Or  the  muriate  may  be  crys 
tallized  without  precipitation  or  dried  in  the  amor- 
phous state  in  a  high  heat.  The  tables  of  the  ox- 
Ids,  or  salts,  will  show  the  exact  proportion  of 
pure  iron. 

N.  B.  Young  analysts  generally  fail  in  this 
analysis,  and  in  some  others,  because  they  do  not 
make  the  powder  of  the  ore  fine  enough,  nor  wait 
long  enough  for  the  solution.  Nothing  but  hard- 
ened steel  is  sufficiently  hard  for  a  mortar,  and 
from  three  to  six  days  are  required  for  solution. 
The  steel  face  of  an  anvil  will  be  sufficient,  if  the 
mineral  is  pounded  in  a  ring  to  prevent  scattering* 
with  a  good  smooth-faced  hammer. 

Pyrites  should  be  boiled  in  nitric  acid  until  the 
sulphur  is  converted  into  sulphuric  acid,  Tht 


ANALYSIS    OF    MINERALS,  259 

sulphuric  acid  is  then  converted  to  sulphate  of 
barytes  by  introducing  muriate  of  bary tes  ;  and  on 
drying  the  precipitated  sulphate  of  barytes  the 
original  proportion  of  sulphur  is  ascertained — al- 
lowing 14.5  of  pure  sulphur  for  100  of  this  dry 
precipitate. 

Subtract  the  sulphur,  thus  ascertained,  from  the 
•whole  mass  under  examination,  and  the  remainder 
is  the  pure  iron,  if  the  pyrites  is  a  pure  per-sul- 
phuret. 

But  specimens  are  rarely  pure  sulphurets. — 
Therefore  it  is  best  to  prove  the  work  by  pouring 
in  a  solution  of  carbonate  of  soda.  This  precipi- 
tate, when  dried  and  weighed,  will  give  the  pure 
iron  after  deducting  the  common  proportion  of 
oxygen  in  protoxid  of  iron. 

If  manganese  is  suspected,  or  any  thing  else, 
use  tests  for  their  presence  respectively.  If  found 
present,  ascertain  their  proportions  in  the  usual 
way  with  such  substances  ;  or  precipitate  the  iron 
with  prussiate  of  potash,  gallic  acid,  or  benzoate 
of  ammonia,  and  examine  the  proportion  of  pure 
Iron  in  this  salt. 

Carburet  of  iron,  (plumbago)  should  be  heated 
in  a  crucible  to  a  high  white  heat.  The  carhou 
will  be  burned  out,  leaving  the  iron  nearly  pure. 

Sulphate  of  iron  (copperas)  should  be  bleated  in 
a  crucible  to  a  high  white  heat.  The  peroxid  of 
iron  will  be  left  in  the  crucible,  which  may  be 
weighed  in  this  dry  state,  and  the  common  deduc- 
tion  made  for  the  oxygen. 

2.  Lead,  in  the  state  of  a  sulphuret,  or  galena, 
should  be  dissolved  in  diluted  nitric  acid — the 
sulphur  will  be  left  undissolved.  The  sulphur 
must  be  dried  and  weighed.  This  deducted,  will 
probably  leave  the  weight  of  pure  lead.  But  the 


260  ANALYSIS   OF  MINERALS. 

muriate  of  lead  may  be  drred  anil  weighed,  and  a 
deduction  made  for  the  proportion  of  muriatic  acid, 
as  set  down  in  the  tables.  If  silver,  antimony,  or 
zinc,  is  suspected,  proceed  to  examine  for  each 
independently  as  directed  under  these  metals. 

3.  Ztinc,  in  the  state  of  a  sulphuret,  (blende) 
may  be  dissolved  in  nitric  acid   and  precipitated 
by  soda.     It  is  best  to  re-dissolve  it  in  muriatic 
acid  and  precipitate  it  again.     If  the  presence  of 
copper  had  appeared  by  the  general  test,  precipi- 
tate it  by  a  plate  of  clean  soft  iron. 

Calamine  may  be  dissolved  in  nitric  acid  and 
precipitated  by  ammonia.  But  it  is  best  to  pre- 
cipitate it  and  evaporate  it  to  dryness  and  dissolve 
it  again  before  it  is  precipitated  for  weighing. 

4.  Copper  pyrites,  may  be  dissolved  by  nitro- 
muriatic  acid,  and  precipitated  from  the  acid  and 
from  the  iron,  &c.  by  the  iron  plate. 

Carbonate  of  copper,  may  be  dissolved  in  nitric 
acid,  and  the  copper  precipitated  with  the  iron 
plate. 

5.  Manganese  peroxid,   is  separated  from  its 
oxygen  with  great  difficulty.     Its  qualities  may 
be  tested  by  making  chlorine   gas  in  the  usual 
way,  with  an  ounce  of  it.     See  how  much  pure 
gas  it  will  produce,  and  compare  it  wifch  another, 
ounce  which  is  known  to  be  good. 

Argillaceous  manganese,  is  the  oxid  of  manga- 
nese combined  with  iron  and  clay.  Try  its  quali- 
ty as  above. 

Both  kinds,  on  being  heated  in  a  gun-barrel, 
give  oVer  carbonic  acid,  before  the  heat  is  raised 
sufficiently  for  eliminating  oxygen.  This  may  be 
collected  ;  and,  as  it  is  produced  from  carbonate 
of  iron,  the  quantity  of  that  ore  may  thus  be  as- 
certained by  the  tables. 


ANALYSIS    OF   MINERALS.  261 

6.  Chromate  of  iron  must  be  melted  with  eight 
or  ten  times  its  weight  of  potash,  and  then  dissolv- 
ed in  water.     This  solution  should  be  saturated 
with  nitric  acid,  to  take  up  the  excess  of  potash. 
Then  put  in  a  solution  of  nitrate  of  lead.  A  double 
decomposition  will  take  place,  and  the  precipitate 
will  be  chromate  of  lead.     After  washing  and 
weighing,  allow  35  of  chromic  acid  for  100  of 
chromate  of  lead. 

7.  Sulphuret  of  silver  is  heated  with  diluted 
nitric  acid.     The  silver  is  dissolved.     But  it  is 
best  to  heat  the  residuum  to  burn  off  the  sulphur  : 
as  some  silver  may  still  remain  with  the  sulphur 
residuum. 

8.  Gold  ores  may  be  heated  with  nitre-muriatic 
acid,  and, precipitated  of  a  purple  colour  with  mu- 
riate of  tin. 

9.  Bismuth  may  be  dissolved  in  nitric  acid,  and 
precipitated  in  the  state  of  a  white  oxid  by  mere 
water. 

10.  Cobalt  should  be  dissolved  in  nitric  acid. 
It  may  then  be  precipitated  with  ammonia.     The 
.precipitate  may  be  dissolved  by  acetic  acid,  form- 
ing an  acetate  of  cobalt.     This  metal  melted  with 
borax  before  the  blow-pipe  or  otherwise,  produces 
a  smalt- blue  glass. 

REMARKS, 

All  the  earthy  minerals  and  the  remaining  ores, 
found  in  this  district  of  country,  can  be  analyzed 
as  far  as  may  be  required,  by  attending  to  the  ex 
ternal  characters  on  using  the  common  tests.  But 
if  very  accurate  investigations  are  required,  largei 
works  must  be  consulted. 


262 

EXTEMPORANEOUS  EXAMINATIONS 

OF  COMMON  SUBSTANCES. 

Sulphuric  acid  blackens  a  pine  stick. 

Nitric  acid  makes  a  pine  stick  whitish  yellow. 

Muriatic  acid,  if  clean,  does  not  colour  a  pine 
stick 

Common  salt  (muriate  of  soda)  when  thrown  up 
on  burning  coals,  snaps  and  gives  a  yellow  flame. 

Glauber's  salts  (sulphate  of  sod-i)  hisses  like 
water  and  becomes  a  compact  efflorescence. 

Saltpetre  (nitrate  of  potash)  roars  and  gives 
brilliancy  to  the  coals. 

Mum  (sulphate  of  alumine  and  potash)  melts 
into  an  inflated  efflorescence. 

Epsom  salts  (sulphate  of  magnesia)  becomes  a 
flocculent  efflorescence. 

Common  magnesia  (carbonate  of  magnesia) 
scarcely  changes  on  ever  so  hot  coals. 

White  vitriol  (sulphate  of  zinc)  snaps  some- 
what like  common  salt,  but  does  not  give  a  yellow 
flame. 

Blue  vitriol,  (sulphate  of  copper,)  if  the  coals 
are  very  hot,  it  gives  a  green  flame  and  becomes  a 
white  powder. 

Copperas  (sulphate  of  iron)  extinguishes  bum 
ing  coals  and  forms  brown  spots  on  them. 

Sugar  of  lead  (acetate  of  lead)  gives  off  smoke, 
but  forms  no  efflorescence. 

Corrosive  sublimate  (per-muriate  of  mercury) 
gives  a  dense  suffocating  smoke;  or  if  it  is  dissolv- 
ed in  water  and  poured  into  lime-water,  it  gives 
an  orange  coloured  precipitate. 

Calomel,  if  dropped  into  a  solution  of  pearlash, 
gives  a  dark  precipitate ;  but  will  not  give  the 
orange  colour  to  lime  water* 


EXTEMPORANEOUS  EXAMINATIONS.          263 

Verdegrls  (acetate  of  copper)  on  being  held  in 
the  flame  of  a  candle,  presents  numerous  red  glo- 
bules. 

Borax  (sub-borate  of  soda)  on  being  held  in  the 
flame  of  a  candle,  boils,  swells,  and  becomes  like 
parched  corn.  This  salt  gives  a  sweetish  taste. 

Iron,  if  dissolved  in  warm  sulphuric  acid,  gives 
a  black  colour  when  dropped  into  an  infusion  of 
nut-galls. 

Manganese  (in  its  common  state  of  a  peroxid)  if 
pulverized,  mixed  with  common  salt,  and  made 
into  a  thin  paste  ;  then  put  into  a  wine  glass,  and 
sulphuric  achs  is  poured  upon  it,  a  suffocating  gas 
of  a  light  green  colour  will  be  given  off.  If  a 
piece  of  calico  is  wet  and  spread  over  the  top  of 
tbe  glass,  the  colour  of  the  calico  will  soon  be  ex- 
tinguished. 

Tin  dissolved  in  nitre-muriatic  acid  changes  a 
purple  solution  of  cochineal  to  scarlet. 

Zinc,  on  being  melted  and  boiled,  becomes  a 
white  woolly  substance,  lighter  than  air. 

Common  arsenic  (arsenious  acid)  gives  the. 
smell  of  garlick,  when  thrdwn  upon  hot  coals. 

Copper,  if  dissolved  in  sulphuric  acid,  becomes 
blue  when  dropped  into  liquid  ammonia. 

Common  sulphur  et  of  antimony,  if  pulverized 
and  mixed  with  saltpetre  and  thrown  upon  a  fire- 
shovel  heated  to  whiteness,  deflagrates  and  be- 
comes a  yellow  mass. 

Bismuth,  if  dissolved  in  nitric  acid,  is  precipi- 
tated in  a  white  powder  if  water  is  added. 

Gold  can  be  dissolved  in  no  acid,  but  the  nitro- 
inuriatic,  and  is  of  a  yellow  colour. 

Platina  can  be  dissolved  in  no  acid  but  nitro* 
muriatic,  and  is  of  a  steel  grey  colour. 


264          EXTEMPORANEOUS  EXAMINATIONS. 

Silver  can  be  dissolved  in  no  single  acid  but  the 
nitric  ;  and  when  the  solution  has  become  clear,  a 
particle  of  common  salt  will  render  it  cloudy. 

Mercury,  if  dissolved  in  cold  nitric  acid,  will 
throw  down  a  white  insoluble  powder  (calomel) 
if  a  solution  of  common  salt  be  poured  into  it. 

Lead,  if  dissolved  in  hot  nitric  acid,  becomes 
Mack  by  pouring  into  it  water  which  is  charged 
•with  sulphuretted  hydrogen. 

The  following  metals,  when  forming  the  bases 
of  salts,  may  be  dissolved  in  pure  water,  and  then 
detected  by  their  various  coloured  precipitates, 
which  are  produced  by  pouring  in  a  solution  of 
prussiate  of  potash. 

Iron  will  give  a  blue  precipitate — manganese, 
peach-bloom — tin,  white — zinc,  white — chrome, 
green — columbium,  olive — bismuth,  white— co- 
]balt,  grass-green — titanium,  yellowish-brown — • 
cerium,  white- — uranium^  blood-red — silver,  white 
becoming  blue — palladium,  olive — iridium,  col- 
ourless— lead,  white — nickel,  milk-white— pro- 
toxid  of  copper,  reddish-brown^  and  peroxid  of 
copper;  white. 


APOTHECARIES'  WEIGHT. 

20  grains  1  scruple — 3  scruples  1  drachm — 3  drachms 
1  ounce — 12  ounces  1  pound. 

MARKS  ON  WEIGHTS. 

o  stands  for  grain — B  for  scruple — 3  for  drachm — 3 
for  ounces — }fo  for  pound — i  or  j  for  one  of  either,  ii  for 
two,  &c. 

FRENCH  WEIGHTS. 

A  millegramme  is  equal  to  .0154  of  a  grain- — a  centi- 
gramme, 0.1544  gr. — a  decigramme,  1.5444  gr. — a 
gramme,  15.4440  gr. — a  decagramme,  154.4402  gr.— 
a hecatogramme,  1544.4023  gr. — a  kilogramme,  15444, 
0234  gr. — a  myriogramme,  154440.2344  gr. 

WEIGHT  OF  GASES. 

Atmospheric  air  being  assumed  as  the  standard  or  uni- 
ty, 100  cubic  inches,  weighing  30  grains  and  20  hun- 
ciredths  of  a  grain.  Atmospheric  air,  1.000 — oxygen, 
1.117 — nitrogen,  0.968 — hydrogen,  0.074 — carbonic 
acid  gas,  1.542 — ammonia,  0.596 — sulphuretted  hydro- 
gen, 1.192 — carburetted  hydrogen,  (olifiant)  0.998 — - 
coal  gas,  0.450 — phosphuretted  hydrogen,  0.894 — chlo- 
rine, 2.495 — muriatic  acid,  1.285 — nitrous  oxid,  (exhi- 
lerating  gas)  1.527— nitric  oxid, '1.043 — nitrous  acid, 
2.135 — sulphurous  acid,  2.235 — prussic  acid,  (hydrocy- 
anic) 0.946— -water  in  vapour,  0.623 — alcohol  in  vapour, 
1;50G — sulphuric  ether  in  vapour,  2.396— spirits  of  tur* 
pentine  in  vapour,  5.013. 

WEIGHT  op  LIQUIDS, 
Water  being  assumed  as  the  standard  or  urtity. 
Sulphuric  ether,  0.76— nitric  etlier>0.9t>— alcohol,  0* 

23 


266  TABLES. 

91— proof  spirits,  0.93— distilled  vinegar,  1—  muriatic 
acid,  concentrated,  1.17 — sulphuric  acid,  1.84 — nitric 
acid,  1.42 — fuming  nitrous  and  nitric  acid,  1.50. 

WEIGHT  OF  SOLIDS. 

Water  being  assumed  as  the  standard  or  unity. 

Potassium,  0.85 — sodium,  0.97 — lime,  2,3 — barytes, 
4 — strontian,  3.7 — magnesia,  2.3 — silex,2.66 — alumine, 
2 — iron,  7.78 — manganese,  6.85 — tin,  7.3 — zinc,  7 — 
cadmium,  8.6 — arsenic,  9.35— chrome,  5.9 — molybdena, 
7.4 — tungsten,  17.5— columbium,  5.91 — copper,  8.9 — 
antimony,  6.7 — bismuth,  9.8 — cobalt,  8 — red  oxid  of 
titanium,  4.2 — tellurium,  6.1 — red  oxid  of  cerium,  4.9 
— uranium,  9. — gold,  19.3 — silver,  10.5— platina,  21. — 
palladium,  11. — rhodium,  11. — iridium,  19.5? — osmi~ 
um,  unknown — mercury,  13.5 — lead,  11.35 — nickel,  8, 
25. 

SIMPLE  AFFINITIES. 

Each  substance,  printed  in  small  capitals,  has  the 
strongest  affinity  for  the  substance  standing  next  to  it*, 
and  this  force  is  weaker  for  the  next,  and  so  in  succes- 
sion. 

OXYGEN.  Carbon,  manganese,  zinc,  iron,  tin,  anti- 
mony, hydrogen,  phosphorus,  sulphur,  arsenic,  nitrogen, 
nickel,  cobalt,  copper,  bismuth,  mercury,  silver,  gold, 
platina,  muriatic  acid. 

OXYGEN.  [Set  down  according  to  the  difficulty  with 
which  it  is  separated  fr^m  metals,  by  heat,  when  com- 
bined by  nature.J 

Titanium,  manganese,  zinc,  iron,  tin,  molybdena,  co- 
balt, antimony,  nickel,  arsenic,  chrome,  bismuth,  lead, 
copper,  platina,  mercury,  silver,  gold. 

CARBON.     Oxygen,  iron,  hydrogen. 

NITROGEN.  Oxygen,  sulphur  ?  phosphorus,  hydro* 
gen. 

HYDROGEN.  Chlorine?  oxygen,  sulphur,  carbon, 
phosphorus,  nitrogen. 


TABLES*  267 

SULPHUR,  PHOSPHORUS?  Potash,  soda,  iron,  cop- 
per, tin,  lead,  silver,  bismuth,  antimony,  mercury,  ar- 
senic, molybdena. 

POTASH,  SODA  and  AMMONIA.  Acids.  Sulphuric  t 
nitric,  muriatic,  phosphoric,  fluoric,  oxalic,  tartaric,  ar- 
senic, citric,  benzoic,  sulphurous,  acetic,  boracic,  car- 
bonic, prussic,  oil,  water,  sulphur. 

BARYTES.  Sulphuric,  oxalic,  fluoric,  phosphoric,  ni- 
tric, muriatic,  citric,  tartaric,  arsenic,  benzoic,  boracic, 
carbonic,  prussic. 

STRONTIAN.  Sulphuric,  phosphoric,  oxalic,  tartaric, 
fluoric,  nitric,  muriatic,  carbonic. 

LIME.  Oxalic,  sulphuric,  tartaric,  phosphoric,  nitric, 
muriatic,  fluoric,  arsenic,  citric,  malic,  benzoic,  boracic, 
carbonic,  prussic,  sulphur,  phosphorus,  water,  fixed  oil 

MAGNESIA.  Oxalic,  phosphoric,  sulphuric,  fluoric, 
nitric,  muriatic,  tartaric,  citric,  benzoic,  acetic,  boracic, 
carbonic,  prussic,  sulphur. 

ALUMINE.  Sulphuric,  nitric,  muriatic,  oxalic,  fluoric, 
tartaric,  citric,  phosphoric,  benzoic,  acetic,  boracic,  car- 
bonic, prussic. 

SILEX.     Fluoric,  potash, 

OXID  OF  PLATINA,  OXID  OF  GOLD.  Gallic,  muri- 
atic, nitric,  sulphuric,  arsenic,  fluoric,  tartaric,  phos- 
jphoric,  acetic,  prussic,  ammonia- 

OXID  OF  SILVER.  Gallic,  muriatic,  oxalic,  sulphu- 
ric, phosphoric,  nitric,  arsenic,  fluoric,  tartaric,  citric, 
acetic,  prussic,  carbonic. 

OXID  OF  MERCURY.  Gallic,  muriatic,  oxalic,  ar- 
senic, phosphoric,  sulphuric,  tartaric,  citric,  malic,  ni- 
tric, fluoric,  acetic,  benzoic,  boracic,  prussic,  carbonic-. 

OXID  OF  LEAD.  Gallic,  sulphuric,  oxalic,  arsenic, 
tartaric,  phosphoric,  muriatic,  nitric,  fluoric,  citric,  mal- 
ic, acetic,  benzoic,  boracic,  prussic,  carbonic,  fixed  oils, 
ammonia. 

OXID  OF  COPPER.  Gallic,  oxalic,  tartaric,  muriat- 
ic, sulphuric,  nitric,  arsenic,  phosphoric,  fluoric,  citric, 
acetic,  boracic,  prussic,  carbonic,  fixed  alkalies,  ammo* 
jnia,  fixed  oils. 


268  TABLES. 

/ 

OXID  OF  ARSENIC.  Gallic,  muriatic,  oxalic,  sul- 
phuric, nitric,  tartaric,  phosphorict  fluoric,  citric,  acetic? 
prussic,  fixed  alkalies,  ammonia,  fixed  oils,,  water. 

Oxip  QF  IRON.  Gallic,  oxalic,  tartaric,  camphoric, 
sulphuric,  muriatic,  nitric,  phosphoric,  arsenic,  fluoric, 
citric,  acetic,  boracic,  prussic,  carbonic. 

OXID  OF  TIN.  Gallic,  muriatic,  sulphuric,  oxalic, 
tartaric,  arsenic,  phosphoric,  nitric,  fluoric,  citric,  acetic, 
boracic,  ammonia,  prussic. 

OXID  OF  ZINC.  Gallic,  oxalic,  sulphuric,  muriatic, 
nitric,  tartaric,  phosphoric,  citric,  fluoric,  arsenic,  acetic, 
boracic,  prussic,  carbonic,  fixed  alkalies,  ammonia. 

OXTD  OF  ANTIMONY.  Gallic,  muriatic,  benzoic,  ox- 
alic, sulphuric,  nitric,  tartaric,  phosphoric,  citric,  fluor- 
ic, arsenic,  acetic,  boracic,  prussic,  fixed  alkalies,  am- 
monia. 

SULPHURIC  ACID,  PRUSSIC.  Barytes,  strontian,  pot- 
ash, soda,  lime,  magnesia,  ammonia?  alumine,  metallic 
oxids. 

PHOSPHORIC  ACID,  CARBONIC.  Barytes,  strontian3 
lime,  potash,  soda,  ammonia,  magnesia,  (attracts  car. 
stronger  than  ammo.)  alumine,  metallic  oxids. 

NITRIC  ACID,  MURIATIC.  Barytes,  potash,  soda, 
strontian,  lime,  magnesia,  ammonia,  alumine,  metallic  oxids. 

FLUORIC  ACID,  BORACIC,  ARSENIC.  Lime,  barytes, 
magnesia,  potash,  soda,  ammonia,  alumine,  silex. 

ACETIC  ACID,  LACTIC.  Barytes,  potash,  soda,  lime, 
ammonia,  magnesia,  metallic  oxids,  alumine. 

OXALIC  ACID,  TARTARIC,  CITRIC.  Lime,  barytes, 
strontian,  magnesia,  potash,  soda,  ammonia,  alumine,  me- 
tallic oxids,  water,  alcohol. 

BENZOIC  ACID.  White  oxid  of  arsenic,  potash,  soda, 
ammonia,  barytes,  lime,  magnesia,  alumine. 

FIXED  OILS.  Lime,  barytes,  potash,  soda,  magnesia, 
oxid  of  mercury,  other  metallic  oxids,  alumine. 

ALCOHOL.  Water,  ether,  volatile  oil,  alkalies,  sulphur- 
ets. 

SULPHURETTED  HYDROGEN.  Barytes,  potash,  soda? 
lime,  ammonia,  magnesia. 


TABLES.  269 

PROPORTIONS  OF  ELEMENTARY  CON* 
STITUENTS. 

BINARY   COMPOUNDS. 

The  oxygen  10  in  all,  excepting  ammonia. 

Water,  1.32  hydrogen— carbonic  acid,  3.77  carb. — 
sulphuric  acid,  6.66  sulphur — phosphoric  acid,  8.7 
phos. — nitric  acid,  3.51  nit. — chlorine,  31.1  mur.  acid — 
ammonia,  17.54  njt.  396  hyd. — soda,  29.1  sodium — po- 
tash, 49.1  potassium— magnesia,  14.6  magnesium — > 
lime,  25.46  calcium — red  oxid  of  iron,  23  iron — green 
oxid  of  iron,  34.5  ir.-— black  oxid  of  copper,  40  cop- 
per— oxid  of  zinc,  41  zinc —  red  oxid  of  mercury,  125.5 
mere. — black  oxid  of  mercury,  251  mere. — litharge, 
129.5  lead — oxid  of  silver,  135  silver. 

TERNARY  COMPOUNDS. 

Subcarbonate  of  ammonia,  27.5  acid  to  21.5am. — 
subcarbonate  of  soda,  27.5  carb.  ac.  to  39.1  soda — sub- 
carbonate  of  potash,  27.5  acid  to  59.1  potash — carbon- 
ate of  lime,  27.54  carb.  acid  to  35.46  lime — carbonate 
of  barytes,  27.5  acid  to  97  barytes — sulphate  of  soda, 
50  acid  to  39.1  soda — sulphate  of  magnesia  (dry)  50 
acid  to  24.6  magn. — ditto  chrystallized,  74.6  sul.  mag. 
to  79.3  water — sulphate  of  barytes,  50  acid  to  97  bary- 
tes— sulphate  of  copper,  50  acid  to  50  copper  to  56.6 
water — sulphate  of  iron,  50  acid  to  34.5  iron  to  79.3 
water — sulphate  of  zinc,  50  acid  to  51  zinc  to  79. 3  water 
— nitrate  of  potash,  67*54  acid  to  59.1  potash — muriate 
of  ammonia,  34.1  acid  to  21.5  am.  to  1K32  water — mu- 
riate of  soda,  34.1  acid  to  39.1  soda — muriate  of  pot- 
ash,  34.1  acid  to  59.1  potash — oxymuriate  of  potash 
93.2  mur.  pot.  to  60  ox. — muriate  of  lime,  34. 1  acid  to 
35.5  lime — muriate  of  barytes,  34  acid  to  97  barytes-*- 
cor.  muriate  of  mercury,  34.1  acid  to  10  ox.  to  125.5 
mere. — submuriate  of  ditto,  34  acid  to  10  ox.  to  25 1 
mere. — sulphate  of  lime  (dry)  50  acid  to  35.5  lime — dit« 
to  crystallized,  85.5  sul.  lime  to  22.4  water. 

23* 


270  TABLES. 

EFFECTS  OF  HEAT  AT  THE  DIFFERENT    DEGREES  OF 
FAHRENHEIT. 

90  degrees  (below  zero)  the  greatest  degree  of  artifi- 
cial cold — 55  nitric  acid  freezes — 50  natural  cold  at 
Hudson's  Bay — 46  ether  ?  and  strong  liquid  ammonia 
freeze — 39  mercury  freezes — 36  sulphuric  acid  freezes — 
0  cold  produced  by  equal  parts  of  snow  and  salt — 25 
(above  zero)  human  blood  freezes — 30  milk  freezes — 32 
water  and  oxy muriatic  acid  freezes — 67  water  boils  in  a, 
vacuum — 97  lurd  melts — 98  blood  heat,  ether  boils — 
107  feverish  heat — 122  phosphorus  burns — 127  tallow 
oielts — 142  beeswax  melts — 176  alcohol  boils — 212  wa- 
ter boils — 442  tin  melts — 476  bismuth  melts — 540  ar- 
senic is  volatilized — 590  sulphuric  acid  boils — 612  lead 
•tnelts — 644  mercury  boils — 700  zinc  melts — 809  anti- 
mony melts — 1077  iron  red  by  daylight — 1892  silver 
melts— 2205  copper  melts — 2517  gold  melts — 6508  iron 
welding  hot— 8696  cast  iron  melts — 10517  manganese 
cnelts — 1 1454  soft  iron  melts — 23177  platina  melts. 

ATOMIC  THEORY. 

RELATIVE   WEIGHT   OF  ATOMS. 

Mr.  Dalton  has  shewn,  that  if  the  weight  of  the  ulti- 
mate indivisible  atom  of  oxygen  be  called  one,  the 
weight  of  the  ultimate  atoms  of  the  following  substances 
ere  proportioned  to  it  as  here  set  down.  Oxygen  I— 
fiitrogen  1.8 — hydrogen  0.13 — carbon  0.75 — phospho- 
rus 2.6 — sulphur.  2 — chlorine  (if  simple)  4.5— -potassium 
6 — sodium  5.88 — calcium  2.6 — barium  8.7 — magnesium 
1.5 — gold  24.9 — platina  12.1 — silver  13.7 — mercury  25 
— copper  8 — iron  7.1 — tin  .14.7 — lead  12.9 — zinc  4 — 
bismuth  9— antimony  11.2 — arsenic  6 — manganese  7.1. 

NUMBER  OF  CONSTITUENT  ATOMS  IN  COMPOUND  SUB- 
STANCES. 

Acids, 

Water,  1  ox.  1  hyd. — carbonic  acid,  2  ox.   1    car.— 
oxid  of  nitrogen,  1  ox.  1  niu— -nitrous  acid,  3  oxe  1  nit 


TABLES.  '271 

--nitric,  acid  5  ox.  1  nit. — phosphoric  acid,  3  ox.  I  phos. 
—sulphurous  acid,  2  ox.  1  sul. — sulphuric  acid,  3  ox.  I 
sill,— oxalic  acid,  3  ox.  2  carbon  and  hydrogen. 

Alkalies. 

Potash,  1  potassium  1  ox. — soda  1  sodium  2  ox. — am- 
monia, 1  nitrogen  1  hydrogen — lime,  1  calcium  1  ox.—- 
magnesia,  1  magnesium  1  ox.— barytes,  1  bar.  1  ox. 

Oxids  of  Metals. 

Protoxid  of  manganese,  1  man.  1  ox. — deutoxid  of 
manganese,  1  man.  2  ox. — tritoxid  of  manganese,  1  man, 
3  ox. — peroxid  of  manganese,  1  man.  4  ox.— deut.  of 
iron,  1  iron  2  ox. — per  iron,  1  iron  3  ox. — pro.  copper,  1 
cop.  2  ox. — per.  copper,  1  cop.  2  ox. — deut.  tin,  1  tin  2 
ox. — tri.  tin,  1  tin  3  ox. — per.  tin,  1  tin  4  ox. — pro.  lead, 
1  lead  1  ox. — deut.  lead,  (red  lead)  2  lead  3  ox. — per. 
lead,  1  lead  2  ox.— pro.  zinc,  (it  has  but  one  degree)  1 
zinc  1  ox. 

Salts. 

Sulphate  of  soda,  1  acid  2  soda— sulphate  of  magne- 
sia, 1  acid  1  mag. — sul.  lime,  1  ac.  1  lime— alum  6  sul- 
phuric acid,  5  alumine  1  potash — sulphateof  copper,  1 
ac.  1  cop. — sulphate  of  iron,  1  ac.  1  iron — sulphate  of 
zinc,  1  ac.  1  zinc — nitpate  of  potash,  1  ac.  !  pot. — nitrate 
of  silver,  1  ac.  1  sil. — nitrate  of  mercury,  1  ac.  1  mer. — 
carbonate  of  ammonia,  ]  PC.  i  am. — carbonate  of  lime, ! 
ac.  1  lime— carbonate  of  magnesia,  1  ac.  1  mag.; 

•'Uret*. 

Sulphuret  of  iron  (cubic)  4  sul.  1  iron— sulphuret  of 
'lead,  1  sul.  1  lead — sulphuret  of  antimony,  2  sul.  1  ant.-*- 
sulphuret  of  zinc,  1  sul.  1  zinc — sulphuret  of  copper,  1  suL 
1  cop. — carburetted  hydrogen,  1  car.  2  hyd. — sulphuret- 
ted hydrogen,  1  .suL  1  hyd.— phospluiretted  hydrogen,  I 
phos.  3  hyde 


INDEX. 


A 

Copperas 

1GS 

Pasre. 

Corrosive  sublimate 

204 

Acidifying  substances 
Aethiops  mineral 

048 
203 

Crocus  of  antimony 
Cyanogen 

186 
216 

Affinity 

16 

D 

Albuirien 

231 

Decarbonate 

233 

Alcohol 

227 

Definite  proportions 

21 

Alkalies 

122 

Diamond 

104 

Alum 

155 

Dough 

2^4 

Alumine 

154 

E 

Ammonia 
Ammoniurel 
Analyses 
Animal  substances 
Antimony 
Apparatus 
Arsenic 
Atmospheric  air 
Atomic  theory 

89,  132 
182 
241 
231 
185 
7 
178 
80 
22 

Earths                                   122, 
Effluvia 
Electricity 
Epsom  salts 
Etching                                    64, 
Ether 
Ethiops  per  SB 
Examinations 
Exhilirating  gaa 

151 
235 
40 
150 
164 
223 
201 
262 
87 

Extractive  matter 

220 

Barytes 

146 

Bell-metal 
Bismuth 

183 
187 

Fermentation 

225 

Bitumen 
Bleaching 
Blood 

225 
58 
232 

Fibrin 
Fixed  oil 
Fluoric  acid 

221 
222 
64 

Blowpipe 
Blue  vitriol 

163 
183 

Fluorine  ' 
Fluor  spar 

ifc. 
ib. 

Bones 
Borax 
Boron 

232 
118 
ib. 

Forge 
Freezing  mixtures 
Fulminating  powders 

8 
36 

197 

Brass 

176,  183 

Furnace 

7 

Bronze 

ib. 

G 

C 

Galvanism 

76 

Calomel 
•Caloric  ' 
Camphor 
Carbon 
Carbonic  acid 
Carburetted  hydrogen 
Charcoal 
Chlorine 
Chrome 
Cistern 

205 
25 
223 
104 
108 
114 
105 
55 
180 
7 

Gas-holder 
Gas-lights 
Gelatine 
Gems 
Gibbsite 
Gilding 
Glass 
Glauber's  salts 
Gluten 
Glycine 

r<   u 

42 
116 
231 
153 
154 
192 
152 
131 
221 
15S 

Classes 

13 

Gold 

191 

Coal  gas 

lie 

Gum 

219 

Cobalt 

189 

11 

Colouring 
Colours 

219 
45 

Hard  soap 
Hard  waters 

131 

243 

Combustion 

51 

Harrowgate 

9G 

Conductors 
Copper 

34 

132 

Hydrogen 
Hydro-sulphutct  of  ammonia 

69 

139 

274 


INDEX. 


f 

Indelible  ink 

296 

Precipitate  per  se 
Proximate  elements 

206 
15,  216,231 

Indigo 

221 

Prusaic  acid 

218,237 

Iodine 

66 

R 

Iron 

Isinglass 

166 
231 

Red  cabbage 
Red  lead 

11 

209 

J 

Jack  o'Lantern 

102 

Red  precipitate 
Resin 

203 
224 

K 

Respiration 

233 

Kelp 

113 

S 

L 

Safety  lamp 

114 

.  Lead 

207 

Sal  ammoniac 

133 

Light 

43 

Saltpetre 

84,  125 

Lime 

139 

Scheele's  green 

184 

Litharge 

209 

Sabacic  acid 

231' 

Living  principle 

214 

Shells 

232 

Lunar  caustic 

195 

Shooting  stars 

104 

M 

Si'.ex 

151 

Magnesia 

1  b  3    147 

Silver 

194 

Manganese 

170 

Soap 

124,  131 

Marsh  miasmata 

114 

Soap  bubbles 

7G 

Massicot 

208 

Soda 

130 

Mercurial  trough 

9 

Soda  water 

109 

Mercury 

200 

Soils 

241,249 

Metalloids 

121 

Starch 

220 

Metals 

160 

Steel 

166,  167 

Meteors 

104 

Strontian 

148 

Mineral  waters 

639,247 

Sugar 

218 

Molybdena 

187 

Sugar  of  lead 

210 

Mordants 

219,240 

Sulphur 

90 

Muriate  of  ammonia 

134 

Sulphuret  of  iron 

16D 

Muriatic  acid 

GO 

Sulphuretted  hydrogen 

94,  185 

N 

Sulphuric  acid 

93 

•Nickel 
Nitric  acid 

211 
tf 

Sulphurous  acid 
Sympathetic  ink 

91 
187 

Nitric  oxid 

86 

T. 

Nitrogen 

79 

Tables 

265 

Nitrous  acid 

86 

Table  salt 

130 

Nitrous  oxid 

86 

Tannin 

21  B 

Nomenclature 

54,  63,  121 

Tartar-emetic 

187 

O 

Tartaric  acid 

217 

Oil 

222,  231 

Thermometer 

33 

§lifiant  gas 

111 

Tin 

171 

rganic  substances 
Orpiment 

15,  213 
178 

Titanium 
Turpeth  mineral 

190 

20  I 

Oxalic  a"cid 

217 

U. 

Oxydables 

66 

Ultimate  elements 

SI.  5,  231 

Oxygen 

49 

\r 

Oxy  muriate 
Oxymuriatic  acid 
P 

u'7'  in 

. 

Vegetable  acids 
Vegetable  substancf  s 

217 
215 

Patent  yellow 

210 

W 

Pearlash 

123 

Water 

77 

Pewter 

172 

Wax 

221 

Philosopher'^  wool 
Phosphorus 
Phosphuretted  hydrogen 
Pinchbeck 

176 
47 
161 
183 

White  lead 
White  nothing 
White  vitriol 
Wood-sorrel 

210 
176 
177 

21" 

Platina 

198 

Z. 

Potash 

123 

ZaffVe 

189 

Powers 

J2.  16 

Zinc 

I"' 

275 

ADDITIONS  AND  CORBECTIONS. 

Directions  for  making  White  Flux  and  Black  Flux* 
[Make  a  reference  to  this  with  a  pencil  at  p.  247.] 
White  flux.  Mix  equal  parts  by  weight  of  saltpetre  an<? 
cream  of  tartar  (supertartrate  of  potash)  and  pulverize  the  mix- 
ture very  fine.  Heat  a  crucible  to  a  high  red,  or  to  a  white, 
heat.  Drop  into  the  hot  crucible  a  teaspoon  of  the  mixture  at 
a  time.  A  detonation  will  ensue  at  every  introduction  of  the 
mixture.  The  tartaric  and  nitric  acids  will  mostly  fly  off,  leav- 
ing potash  almost  pure.  This  must  be  closely  corked  up  in  a 
vial,  to  be  used  for  aiding  in  the  fusion  of  some  minerals,  &c. 
when  no  oxygen  is  to  be  diseagaged. 

Black  flux.  Mix  saltpetre  with  double  its  weight  of  cream 
of  tartar,  and  pulverize  the  mixture.  Drop  this  mixture  into 
the  hot  crucible  as  directed  in  making  white  flux.  In  this  case 
some  of  the  tartaric  acid  will  be  decomposed  and  charcoal  pro- 
duced in  very  intimate  combination  with  potash.  This  must 
be  closely  corked  up  in  a  vial,  to  be  used  when  oxygen  of  a 
metalic  oxid  is  to  be  disengaged  by  ite  combination  with  the 
charcoal,  while  the  potash  assists  the  process  of  fusion. 

Spelling. — Sufficient  attention  has  not  been  given,  in  this 
book,  to  uniformity  in  spelling.  We  have  authorities  for  dif- 
ference in  spelling  several  technical  names.  As  chlorin  or 
chlorine,  oxigen,  oxygen,  or  oxygene.  Some  one  of  the  author- 
ized kinds  of  spelling  ought  to  have  been  selected,  and  pursued 
uniformly. 


Page  14-line  16,  "  or"  should  be  of,  and  be  preceded  by  a  comma. 

32— line  3  from  the  bottom,  "  liquids"  should  be  solids. 

— —  35 — line  14  and  15,  a  comma  must  be  placed  after  the  words  "  scratch^ 

and  •'  smoke." 

102— line  5  from  the  bottom,  "  Prop.  7."  should  be  Prop.  8. 

119— line  8  from  the  bottom,  "  soluble"  should  be  globule. 

247— line  7,  "  vegetade"  should  be  vegetable.    On  the  same  page,  after 

the  word  "  blow-pipe"  add,  See  Additions  and  Corrections,  p.  275, 


M.amxa\  oi 

A  fifth  edition  of  this  work  will  soon  be  through  the  press  of 
Messrs.  WEBSTERS  and  SKINNERS.  It  will  embrace  all  known 
indigenous  plants  growing  north  of  the  Gulf  of  Mexico,  and  the 
common  cultivated  exotics. 

The  descriptions  will  be  considerably  improved  and  con- 
densed ;  so  that  the  work  will  hot  be  much  enlarged,  though  it 
will  embrace  almost  double  the  number  of  species. 

So  many  books  have  been  published  with  enlarged  descrip- 
tions of  North  American  plants,  within  a  few  years,  that  a 
portable  system  may  be  conveniently  used  with  occasional  refer- 
ences to  such  books,  if  the  descriptions  are  considerably  con- 
densed. It  is  hoped,  that  the  price  need  not  be  materially  en- 
creased  ;  but  this  cannot  be  accurately  ascertained,  until  it  is 
finished.  It  will  contain  the  grammar,  natural  orders,  &c.  the 
same  as  before.  But  the  whole  Botanical  Dictionary,  trans- 
lated from  the  French  of  Richard,  and  published  by  Gen. 
Howe,  in  New-Haven,  in  the  year  1819,  with  some  improve- 
ments, will  be  published  at  the  end  of  the  book.  It  will  contain 
short  descriptions  of  all  the  established  southern  and  western 
species  of  Elliot,  Nuttall,  Torrey,  James,  Beck,  Pursh,  Muh- 
lenberg,  Darlington,  Baldwin,  Schwimtz,  Halsey,  Rafinesque, 
and  others. 


, 


Motfiester,  W.  T, 


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